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Recent studies have indicated that Eastern China might be a potential source region of increased atmospheric chlorofluorocarbons (CFCs). To investigate this possibility, a field measurement was carried out from October to December 2017 for identifying the ambient concentration levels of representative trichlorofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12), trifluorotrichloroethane (CFC-113), and tetrafluorodichloroethane (CFC-114) at the residential and municipal solid waste (MSW) landfills and industrial sites in Eastern China. The ambient mixing ratios of CFCs at residential sites were almost within 20% enhancements of the global background sites. The highest levels of CFCs were observed at the MSW landfill sites. Moreover, CFC-11 and CFC-113 concentrations at MSW landfill, which was in service, were two times higher than that at completed MSW landfill. Mean concentrations of 322 pptv for CFC-11, 791 pptv for CFC-12, 91 pptv for CFC-113, and 16 pptv for CFC-114 at various industrial sites were higher than those at residential sites, but they were obviously lower than that at MSW landfill in use. A poor intercorrelation between the CFCs indicated that they did not come from the same source. Higher concentrations measured in this study compared with background sites indicates that MSW landfills could be an unintentional emission source and there are still substantial amounts of CFCs being stored in banks that may discharge CFCs into the atmosphere in Eastern China.

Porous materials are widely used in industry for applications that include chemical separations and gas scrubbing. These materials are typically porous solids, although the liquid state can be easier to manipulate in industrial settings. The idea of combining the size and shape selectivity of porous domains with the fluidity of liquids is a promising one and porous liquids composed of functionalized organic cages have recently attracted attention. Here we describe an ionic-liquid, porous, tetrahedral coordination cage. Complementing the gas binding observed in other porous liquids, this material also encapsulates non-gaseous guests-shape and size selectivity was observed for a series of isomeric alcohols. Three gaseous chlorofluorocarbon guests, trichlorofluoromethane, dichlorodifluoromethane and chlorotrifluoromethane, were also shown to be taken up by the liquid coordination cage with an affinity that increased with their size. We hope that these findings will lead to the synthesis of other porous liquids whose guest-uptake properties may be tailored to fulfil specific functions.

Hourly atmospheric measurements of halocarbons and chlorofluorocarbon (CFC) replacements were conducted at an urban site of Lukang, Changhua, in central Taiwan from May to August, 2013. The temporal distribution of different groups of halocarbons in the Lukang urban atmosphere, including chlorofluorocarbons (CFCs), Chlorodifluoromethane (HCFC-22), Bromochlorodifluoromethane (Halon-1211), and other chlorinated compounds, is presented and discussed. The concentrations (mixing ratios) of HCFC-22, Dichlorodifluoromethane (CFC-12), Halon-1211, Trichlorofluoromethane (CFC-11), Dichloromethane (CH 2 Cl 2 ), and Trichloroethylene (TCE) were enhanced with respect to the local background levels; the atmospheric mixing ratio of carbon tetrachloride (CCl 4 ) was slightly higher than its local background level; on the other hand, 1,1,2-Trichlorotrifluoroethane (CFC-113) was relatively uniform and not very different from background atmospheric level in non-urban areas. Among these compounds, HCFC-22, Halon-1211 and the halogenated compounds, CH 2 Cl 2 and TCE, used as solvents were strongly enhanced. The average mixing ratio of Halon-1211 was higher than the local background of ∼4.5 ppt by ∼60% although Halon-1211 production had been phased out by 1996. Hourly average mixing ratios of halocarbons (HCFC-22, CFC-12, Halon-1211, CFC-11, CH 2 Cl 2 , and TCE) illustrated a distinct diurnal cycle characterized with a pattern of elevated mixing ratio and large mixing ratio variability amplitude at night relative to that in daytime. Although emission sources of these halocarbons were complex, hourly average mixing ratios for most of these high variability halocarbons peaked at ∼5:00 AM when the hourly average wind speed reached the minimum value of the day; by contrast, the hourly average mixing ratio of CO peaked at ∼8:30 AM when the ambient atmospheric wind condition was strongly influenced by sea breezes during the traffic rush hours. This phenomenon revealed that meteorological factors predominated the distribution of halocarbon mixing ratio in the urban atmosphere and the traffic emission of CFC-12 derived from old vehicles manufactured before 1994 was insignificant to the CFC-12 mixing ratio in the urban atmosphere. The meteorological condition of nighttime atmospheric temperature inversion and low wind speed facilitated the accumulation of terrestrial airborne pollutants near the ground; consequently the hourly average mixing ratios at night were higher than those in daytime by up to ∼2% (CFC-11), ∼7% (CFC-12), ∼75% (HCFC-22), ∼72% (Halon-1211), ∼280% (CH 2 Cl 2 ), and ∼155% (TCE).

Although many studies have been conducted in recent years on the emissions of chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and hydrofluorocarbons (HFCs) at the large regional (such as East Asia) and national scales, relatively few studies have been conducted for cities or metropolitan areas. In this study, 192 air samples were collected in the Pearl River Delta (PRD) region of China in November 2010. The atmospheric mixing ratios of six halocarbons were analyzed, including trichlorofluoromethane (CFC-11, CCl3F), dichlorodifluoromethane (CFC-12, CCl2F2), monochlorodifluoromethane (HCFC-22, CHClF2), 1,1-dichloro-1-fluoroethane (HCFC-141b, CH3CCl2F), 1-dichloro-1,1-fluoroethane (HCFC-142b, CH3CClF2), and 1,1,1,2-tetrafluoroethane (HFC-134a, CH2FCF3), and their emissions were estimated based on an interspecies correlation method using HCFC-22 as the reference species. The results showed no significant change in the regional concentration and emission of CFC in the past 10years, suggesting that the continuous regional emission of CFC has had no significant effect on the CFC regional concentration in the PRD region. Concentrations and emissions of HCFCs and HFCs are significantly higher compared to previous research in the PRD region (P

Comparing the data sets of chemical transient tracers (trichlorofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12), sulfur hexafluoride (SF6)) among three reobservations from 1993 to 2006 in the Okhotsk Sea, we found the remarkable change in the efficiency of oceanic absorption of anthropogenic carbon (EF) based on the observed change of apparent tracer age. EF above 27.0 sigma(theta) increased by 16 % while EF below 27.0 sigma(theta) declined by 27 % during the period from 1993 to 2006. Consequently, EF in the entire water column decreased by 14 %. We concluded that the recent reinforcement of ocean stratification derived from the ocean warming caused the weakening of water ventilation in this region, indicating that the penetration of atmospheric anthropogenic carbon to the deep ocean interior is becoming difficult. Citation: Watanabe, Y. W., J. Nishioka, and T. Nakatsuka (2013), Decadal time evolution of oceanic uptake of anthropogenic carbon in the Okhotsk Sea, Geophys. Res. Lett., 40, 322-326, doi:10.1002/grl.50113.

Odour pollution caused by municipal solid waste is a public concern. This study quantitatively evaluated the concentration, environmental impacts, and olfaction of volatile trace compounds released from a waste transfer station. Seventy-six compounds were detected, and ethanol presented the highest releasing rate and ratio of 14.76 kg/d and 12.30 g/t of waste, respectively. Life cycle assessment showed that trichlorofluoromethane and dichlorodifluoromethane accounted for more than 99% of impact potentials to global warming and approximately 70% to human toxicity (non-carcinogenic). The major contributor for both photochemical ozone formation and ecotoxicity was ethanol. A detection threshold method was also used to evaluate odour pollution. Five compounds including methane thiol, hydrogen sulphide, ethanol, dimethyl disulphide, and dimethyl sulphide, with dilution multiples above one, were considered the critical compounds. Methane thiol showed the highest contribution to odour pollution of more than 90%, as indicated by its low threshold. Comparison of the contributions of the compounds to different environmental aspects indicated that typical pollutants varied based on specific evaluation targets and therefore should be comprehensively considered. This study provides important information and scientific methodology to elucidate the impacts of odourant compounds to the environment and odour pollution.

The growing awareness of climate change/global warming, and continuing concerns regarding stratospheric ozone depletion, will require continued measurements and standards for many compounds, in particular halocarbons that are linked to these issues. In order to track atmospheric mole fractions and assess the impact of policy on emission rates, it is necessary to demonstrate measurement equivalence at the highest levels of accuracy for assigned values of standards. Precise measurements of these species aid in determining small changes in their atmospheric abundance. A common source of standards/scales and/or well-documented agreement of different scales used to calibrate the measurement instrumentation are key to understanding many sets of data reported by researchers. This report describes the results of a comparison study among National Metrology Institutes and atmospheric research laboratories for the chlorofluorocarbons (CFCs) dichlorodifluoromethane (CFC-12), trichlorofluoromethane (CFC-11), and 1,1,2-trichlorotrifluoroethane (CFC-113); the hydrochlorofluorocarbons (HCFCs) chlorodifluoromethane (HCFC-22) and 1-chloro-1,1-difluoroethane (HCFC-142b); and the hydrofluorocarbon (HFC) 1,1,1,2-tetrafluoroethane (HFC-134a), all in a dried whole air sample. The objective of this study is to compare calibration standards/scales and the measurement capabilities of the participants for these halocarbons at trace atmospheric levels. The results of this study show agreement among four independent calibration scales to better than 2.5% in almost all cases, with many of the reported agreements being better than 1.0%.

Measurements of three chlorofluorocarbons (CFCs): trichlorofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12) and trichlorotrifluoroethane (CFC-113), along with methyl chloroform (CH3CCl3) and carbon tetrachloride (CCl4) were made in water samples from Lake Washington, using Electron Capture-Gas Chromatography (EC-GC). The samples were collected in mid-autumn, a period when the lake's upper layer undergoes rapid cooling. At the time of sampling, a strong vertical temperature gradient was present in the lake, with surface temperatures of ∼14°C, and near bottom (50 meters) temperatures of ∼8°C. The concentrations of dissolved CFC-12 and CFC-11 increased with depth, as expected from the higher solubilities of these gases at lower temperatures. Atmospheric measurements made at the sampling site at the time of the cruise, showed that CFC-11 and CFC-12 saturations in the near surface samples were 100 % and 106 %, respectively. For the deepest sample (52 meters) CFC-11 and CFC-12 saturations were 102 % and 126 %. Because the surface layer of the lake responds to changes in atmospheric CFCs on a time scale of several weeks, the higher than equilibrium concentrations of CFC-12 observed at the time of sampling may reflect earlier episodes of elevated levels of atmospheric CFC-12 in this urban area. High concentrations of dissolved CFCs in runoff or industrial effluent might also lead to elevated CFC levels in the lake. The cold, deep water of Lake Washington is relatively isolated from the effects of surface gas exchange except during winter, and the supersaturations observed in the deep layer may reflect periods of elevated atmospheric CFC-12 levels from the previous winter season. These results were compared to summertime profiles of CFC-11 and CFC-12 made in 1994.

The biodegradation of volatile fully chlorofluonnated hydro carbons (CFCs), partly chlorofluorinated hydrocarbons (H CFCs) and vinyl chloride (VC) were investigated in compost and marl in laboratory studies. Trichlorofluoromethane (R11), dichlorodifluoromethane (R12), 1,1,2-trichlorotriflu oroethane (R113), difluoromethane (R32) and VC were bio degradable in compost under anaerobic conditions, probably by methanogenic bacteria. The anaerobic decomposition products of R11 were dichlorofluoromethane (R21 ) and chlo rofluoromethane (R31). The degradation product of R12 was chlorodifluoromethane (R22). R11 and its degradation prod ucts have the inhibiting effects of the R12 degradation under anaerobic conditions. The partly halogenated hydrocarbon R22 and VC were degraded preferentially under aerobic con ditions in marl, probably by methanotrophic bacteria. Under aerobic conditions R22 and VC have inhibited the biodegra dation of methane by methanotrophic bacteria.

Micellar solubilisation was used to enhance the solubility of salbutamol (SB) and triamcinolone acetonide (TAA) in chlorofluorocarbon solvents with the aim of formulating solution metered dose inhaler (MDI) products of these drugs. Stable, isotropic solutions of soya phosphatidylcholine (SPC) were obtained in trichlorotrifluoroethane (P113) and a 30:70 mixture of trichlorofluoromethane (P11) and dichlorodifluoromethane (P12) containing water at a maximum level of R (mol water/mol SPC) = 4. The solubility of SB and TAA in both the non-pressurised solvent (P113) and the pressurised mixture (Pll/P12) increased proportionately with SPC concentration but was reduced on increasing values of R . The incorporation of a charged lipid, dicetyl phosphate, into the micellar structure promoted the solubilisation of SB in both solvent systems. In SPC solutions, the optimal solubility of either drug was achieved at R value of 0.9. Solution MDI formulations of SB and TAA gave reproducible shot potency throughout the pack-life, comparable to the performance of commercially available suspension products (SB, Ventolin; TAA, Azmacort). In contrast to suspension systems, however, there was no loss of potency in the first spray actuated after storage with SB solution MDIs. The respirable fraction (RF) of drug emitted from solution MDIs was significantly increased by altering the orifice diameter of the actuator. These studies confirmed that the highest RF values (in excess of those achieved with suspension products) were achieved when the MDIs were fired through an actuator with the smallest (0.25 mm) orifice.

Publisher Summary Volatile organic compounds are defined as organic compounds that participate in photochemical reactions. The Environmental Protection Agency (EPA) considers several organic compounds to have negligible photochemical reactivity, including methane, ethane, 1,1,1-trichloroethane, methylene chloride, trichlorofluoromethane, dichlorodifluoromethane, chlorodifluoromethane, trifluoromethane, thrichlorotriflhuoroethane, dichlorotetrafluoroehane, and chloropentafluoroethane. Controlling fugitive volatile organic compound (VOC) emissions through the implementation of a leak detection and repair (LDAR) program have been in practice at RasGas Company Limited (RasGas). An LDAR program is designed to identify pieces of equipment that are emitting sufficient amounts of material to warrant reduction of the emissions through repair. The program was initiated by RasGas, on a voluntary basis, on the basis of acceptable environmental practices in other countries susceptible to ozone formation. The United States Environmental Protection Agency (EPA) reports that VOCs contribute to the formation of ground level ozone, which is a major component of smog, and causes or aggravates respiratory disease, particularly in children, asthmatics and healthy adults who participate in moderate exercise. The Ras Laffan Industrial City (RLC) Environmental Regulations implemented fugitive monitoring and reporting requirements for petroleum plant processing equipment, including valves, pump and compressor seals, pressure relief valves, open-ended lines and sampling connection systems.

In laboratory studies, trichlorofluoromethane (F-11), dichlorodifluoromethane (F-12), and 1,1,2-trichlorotrifluoroethane (F-113) were degraded by microbial activity in anaerobic sludges and F-11 and F-113 were degraded in sediments. Biomass acclimated to chlorinated organics degraded chlorofluorocarbons faster than unacclimated biomass. Up to 9% of all CFCs may ultimately be susceptible to biological degradation before release to the atmosphere.

The first cholroflurocarbon (CFC), CFC-12 (dichlorodifluoromethane, CCl2F2), was invented by Thomas Midgley, Jr. and Alfred Henne in 1928 by the fluorination reaction of carbon tetrachloride with antimony trifluoride, and immediately after it was identified as a best refrigerant in performance, CFC-12 was commercialized in 1930 in Du Pont Company as a nonflammable and nontoxic refrigerant to replace toxic refrigerants such as ammonia and sulfur dioxide in electric refrigerators (Giunta 2006). After the invention of CFC-12, other industrially important CFCs, CFC-11 (trichlorofluoromethane, CCl3F), and CFC-113 (trichlorotrifluoroethane, CCl2CClF2) were successively introduced into the market during 1930s–1940s.

Reverse micellization of nonionic surfactants in apolar media was applied to the formulation of solution phase, pressurized inhalation aerosols, employing soya lecithin (SPC) and water in chlorofluorocarbon (CFC) blends. The use of a 30/70 mixture of trichlorofluoromethane (Pll) and dichlorodifluoromethane (P12) resulted in the formation of stable, isotropic systems containing 0.5–2.0% (w/v) SPC and solubilized water; R (moles water/moles SPC), 0.9 to 4.28. In systems containing

A gas chromatographic study has revealed the presence in volcanic gases of a variety of volatile organic compounds. Of particular interest is the detection of such halocarbons as trichlorofluoromethane (F-11), dichlorodifluoromethane (F-12), dichlorofluoromethane (F-21), CCl4 and CHCl3. The concentrations of these compounds attaining 160 ppb in undilute solfataric gases were determined for the first time. The data obtained confirm the existence of a natural source of halocarbons that have a long lifetime in the troposphere and that play an important role in the greenhouse effect and in the catalytic cycle of destruction of stratospheric ozone.

The kinetics and reaction mechanisms of the decomposition of CFCl{sub 3} and CF{sub 2}Cl{sub 2} induced by a continuous CO{sub 2} laser are examined and compared with previous results for CF{sub 3}Cl. All three compounds clearly exhibit two temperature regimes, with similar reaction mechanisms in the low-temperature regimes and significantly different mechanisms in the high-temperature regimes.

Environmental scientists from federal agencies, such as the National Oceanic and Atmospheric Administration (NOAA), and academia have long suspected that increasing anthropogenic inputs of various trace gases into the atmosphere can cause changes in the earth's climate and protective ozone layer. Nitrous oxide and methane, cited in the Kyoto Protocol, as well astrichlorofluoromethane (CFC-11) and dichlorodifluoromethane (CFC-12), cited in the Montreal Protocol, are all greenhouse gases and are implicated in the destruction of the stratospheric ozone layer. The lack of national standards prompted research to determine the feasibility of preparing accurate and stable standards containing these four compounds. Development of these standards would support the measurement of these species by those in the atmospheric research community not having their own source of standards. A suite of eight primary gas standards containing methane, nitrous oxide, CFC-11, and CFC-12 in a balance of air were prepared gravimetrically to bracket the ambient atmospheric concentrations. The combined uncertainties (uc) were calculated from error propagation analysis that included the weighing data from the gravimetric preparation and other sources of error such as the purity analysis of the compounds and air matrix. The expanded uncertainties (U) for the gravimetric standards were < 0.5% as calculated from the equation U = kuc, where the coverage factor k is equal to 2 for a 95% confidence interval. Analyses of the suite of standards by gas chromatography with flame-ionization and electron capture detection resulted in average absolute residuals of < 0.25% from regression models. The NIST suite of eight gravimetric standards was used to determine the concentrations in two standardsfrom NOAA. Those analyses resulted in bias across the two laboratories of < or = 2.1%.

The growing awareness of climate change/global warming and continuing concerns regarding stratospheric ozone depletion will require future measurements and standards for many compounds, in particular halocarbons that are linked to these issues. In order to track and control the emissions of these species globally in the atmosphere, it is necessary to demonstrate measurement equivalence at the highest levels of accuracy for assigned values of standards. This report describes the results of a key comparison for several of the more important halocarbons at atmospheric concentration levels. The comparison includes the chlorofluorocarbons (CFCs) dichlorodifluoromethane (CFC 12), trichlorofluoromethane (CFC 11), and 1,1,2 trichlorotrifluoroethane (CFC 113); the hydrochlorofluorocarbons (HCFCs) chlorodifluoromethane (HCFC 22) and 1-chloro-1,1-difluoroethane (HCFC 142b); and the hydrofluorocarbon (HFC) 1,1,1,2 tetrafluoroethane (HFC 134a), all in a dried whole air sample. The objective of this key comparison is to compare the measurement capabilities of the participants for these halocarbons at trace atmospheric levels. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

The growing awareness of climate change/global warming and continuing concerns regarding stratospheric ozone depletion will require future measurements and standards for many compounds, in particular halocarbons that are linked to these issues. In order to track and control the emissions of these species globally in the atmosphere, it is necessary to demonstrate measurement equivalence at the highest levels of accuracy for assigned values of standards. This report describes the results of a pilot study between National Metrology Institutes and atmospheric research laboratories for several of the more important halocarbons at atmospheric concentration levels. The comparison includes the chlorofluorocarbons (CFCs) dichlorodifluoromethane (CFC 12), trichlorofluoromethane (CFC 11), and 1,1,2-trichlorotrifluoroethane (CFC 113); the hydrochlorofluorocarbons (HCFCs) chlorodifluoromethane (HCFC 22) and 1-chloro-1,1-difluoroethane (HCFC 142b); and the hydrofluorocarbon (HFC) 1,1,1,2-tetrafluoroethane (HFC 134a), all in a dried whole air sample. The objective of this key comparison is to compare the measurement capabilities of the participants for these halocarbons at trace atmospheric levels. Main text. To reach the main text of this paper, click on Final Report. The final report has been peer-reviewed and approved for publication by the CCQM.

This work presents an approach for the derivation of aquatic toxicity values (e.g., EC50, LC50) for chemical contaminants based on literature data and application of structure activity relationship (SAR) equations. Information on chemical and physical properties, environmental fate, and supporting information for water quality guideline/criteria for trichlorofluoromethane and dichlorodifluoromethane was obtained following a comprehensive literature review. A discussion of the applicability of the US EPA ECOSAR software program, uncertainties, and the impact of derived aquatic toxicity values on the development of groundwater generic criteria for the chemicals of interest is provided.

Trichlorofluoromethane (CCl3F; CFC-11) and dichlorodifluoromethane (CCl2F2; CFC-12) have been widely used as tracers of oceanic circulation and mixing on decadal timescales. In order to estimate their transfer rate across the air-sea interface, liquid-phase diffusion coefficients are needed In this study the diffusivities of CFC-11 and CFC-12 in pure water were measured over the temperature range 0.6–30°C. Diffusivities of CFC-11 in pure water ranged from (5.24±0.25)×10−6 cm2S−1 at 0.6°C to (1.13±0.05)×10−5 cm2S−1 at 30.3°C and a fit to the data yielded the equation D CFC-11 = 0.015 exp (−18.1/RT), where R is the universal gas constant in kJ mol−1 K−1 and T is the temperature in Kelvin. Diffusivities of CFC-12 in pure water ranged from (5.38±0.22)×10−6 cm2 s−1 at 0.6°C to (1.26±0.05)×10−5 cm2 s−1at 30.3°C and the temperature dependence can be expressed as DCFC-12= 0.036 exp (−20.1/RT). The estimated uncertainty in both equations is

The biological degradation of volatile halogenated hydrocarbons (chlorocarbons (VCCs) and chlorofluorocarbons (CFCs)) was investigated under simulated conditions of landfills in laboratory test digesters. Fully halogenated VCCs (tetrachloroethylene, 1,1,1-trichloroethane, tetrachloromethane and dichloromethane) and CFCs (trichlorofluoromethane (R11), dichlorodifluoromethane (R12) and 1,1,2-trichlorotrifluoroethane (R113)) were degraded under anaerobic conditions in addition to the methanogenic bacteria in municipal solid waste (MSW) and organic wastes. These substances showed different degradation reactions in the simulated acid and methanephases of MSW landfills. It is assumed that R11 and R113 could be decomposed completely under methanogenic conditions. Dichlorofluoromethane (R21) was oberved as the reductive degradation product of R11 and was further degraded during the methanephase, but hardly at all under acid conditions. Chlorodifluoromerhane (R22) as a degradation product of R12 was not degraded, even not in the methanephase. In the acidphase, R11 was the only CFC to be dechlorinated, although only in small quantities. The degradation products of tetrachloroethylene differed under the various environmental conditions. In the acidphase, 1,1-dichloroethylene was detected as the only dichloroethylene, whereas in particular cis-1,2-dichloroethylene but also trans-1,2-dichloroethylene, 1,1-dichloroethylene and vinyl chloride could be detected as metabolites in the methanephase. Dichloromethane and chloroethane, as metabolites of 1,1,1-trichloroethane, could hardly be degraded at all in the acidphase. The degradation of VCCs and CFCs is largely independent of the substrate used. The investigations have demonstrated that the measured biodegradation rates (0.3–15 mg/m3 material vol./h) cannot be improved considerably since they are limited by the inhibiting effect of the substances and their degradation products.

This report describes organic analyses results from in situ samples obtained from the headspace of the Hanford waste storage Tank 241-C-109 (referred to as Tank C-109). The results described here were obtained to support safety and toxicological evaluations. Organic compounds were quantitatively determined. Thirteen organic tentatively identified compounds (TICs) were observed above the detection limit of (ca.) 10 ppbv, but standards for most of these were not available at the time of analysis, and the reported concentrations are semiquantitative estimates. In addition, the authors looked for the 40 standard TO-14 analytes. Of these, only one was observed above the 2-ppbv calibrated instrumental detection limit. However, it is believed, even though the values for dichlorodifluoromethane and trichlorofluoromethane are below the instrumental detection limit, they are accurate at these low concentrations. The six analytes account for approximately 100% of the total organic components in Tank C-109. These six organic analytes with the highest estimated concentrations are listed in Summary Table 1. Detailed descriptions of the results appear in the text.

We have measured experimental liquid densities and enthalpy increments for an equimolar mixture of trichlorofluoromethane (R-11) + dichlorodifluoromethane (R-12). We have used a continuously weighed pycnometer for measuring the liquid densities and a thermoelectric flow calorimeter for measuring the enthalpy increments. The temperature range for all measurements is from (230 to 425) K. The experimental measurements range up to 69 MPa with the pycnometer and 6.8 MPa with the calorimeter, respectively.

A simple and safety gas exposure method was developed using a gas sampling bag as an exposure vessel and a preparation vessel of diluted gas. The gas exposure conditions such as amount of S9 in the plate, volume of gas for the plate, amount of top agar, exposure period and exposure temperature were examined by mutagenicity testing of 1,3-butadiene using the gas sampling bag. Mutagenicity tests of 14 compounds and 1,3-butadiene on S. typhimurium TA98, TA100, TA1535 and TA1537, and E. coli WP2 uvrA were also examined by the developed gas exposure method. 1,3-Butadiene, propyne (methyl acetylene), monochlorodifluoromethane, ethylchloride, diborane and silane were mutagenic. 1-Butene, 2-butene, 2-methylpropene, methyl vinyl ether, trichlorofluoromethane, dichlorodifluoromethane, 1,2-dichloro-1,1,2,2-tetrafluoroethane, 1,1-difluoroethane and phosphine were not mutagenic on S. typhimurium TA98, TA100, TA1535 and TA1537, and E. coli WP2 uvrA with or without metabolic activation. These results were compatible with a previous report, and this developed method has the advantage that it can be tested easily and safely for combustible and self-combustible substances such as 1,3-butadiene and silane.

Reports on fatalities of chlorofluorocarbons usually involve chlorotrifluoroethane, trichlorofluoromethane, dichlorodifluoromethane or chlorodifluoromethane, where analysis was done using packed column gas chromatography. In this case a death was caused by an azeotropic mixture of chlorodifluoromethane and chloropentafluoroethane, a combination that has not previously been reported in the forensic literature. This report details the analysis using mass selective detection employing capillary gas chromatography columns currently used in many toxicology laboratories. Postmortem toxicology revealed blood concentrations of chlorodifluoromethane and chloropentafluoroethane of 71 mg/L and 0.30 mg/L, respectively. Brain, liver, and lung concentrations of chlorodifluoromethane were (mg/kg) 2.8, 4.4, and 1.6, respectively. Brain, liver, and lung concentrations of chloropentafluoroethane were (mg/kg) 0.80, 0.80, and 0.11, respectively. The victim's blood contained 5.5 mg/L caffeine. Lidocaine, used in resuscitation attempts, was also present in the victim's blood. No other alkali-extractable drugs or volatile alcohols were detected in the victim's blood. The cause of death was acute respiratory arrest due to chlorofluorocarbon inhalation.

Radiocarbon-labeled trichlorofluoromethane (FC-11; 14CC13F) and dichlorodifluormethane (FC-12; 14CC12F2) were separately inhaled by a female subject and a male subject. A predetermined volume of fluorocarbon (1000 ppm; 100 muCi) in air was delivered through a nonrebreating system and a tight-fitting face mask for 7-17 minutes. Total expired gases were collected during fluorocarbon exposure and afterward until no radioactivity was detectable. Expired 14CO2 and 14C-fluorocarbon were assayed. Urine was collected for 72 hours and assayed for nonvolatile radioactivity. Total recoveries of FC-11 were 99.5 and 79.4 per cent in the woman and the man, respectively. Total recoveries of FC-12 were 95.4 and 103.2 per cent. Traces of radioactivity were found in urine (FC-11, 0.07 and 0.09 per cent; FC-12, 0.02 and 0.03 per cent) and in exhaled carbon dioxide (FC-11, 0.13 and 0.10 per cent; FC-12, 0.08 per cent in both subjects). Total metabolites were equal to or less than 0.2 per cent of the administered dose. The amount of radioactivity in urine was insufficient to permit identification of possible fluorocarbon metabolites. The trace of metabolites could be products of radiolabeled impurities. (Key words: Gases, non-anesthetic, dichlorodifluoromethane (Freon 12); Gases, non-anesthetic, trichlorofluoromethane (Freon 11); Pharmacology, fluorocarbons.)

Samples of air have been collected over Britain and its coastal waters in areas remote from anthropogenic sources of pollution and analysed for trichlorofluoromethane, dichlorodifluoromethane and carbon tetrachloride. The samples were collected during 1975 and early 1976 at altitudes of up to 8000 m. The overall mean background levels for these compounds for the period March-August 1975 inclusive was found to be 169 ± 30 pptv ∗ for trichlorofluoromethane, 231±36 pptv for dichlorodifluoromethane and 59 ± 9 pptv for carbon tetrachloride. The mean backgrounds for the period January–February 1976, inclusive, were 165 ± 8 for trichlorofluoromethane, 240±20 for dichlorodifluoromethane and 65 ± 4for carbon tetrachloride.

The orthobaric liquid densities of six halogenated hydrocarbons: trichlorofluoromethane (CCl 3 F), dichlorodifluoromethane (CCl 2 F 2 ), chlorodifluoromethane (CHClF 2 ), 1,1,2-trichlorotrifluoroethane (CCl 2 FCClF 2 ), 1,2-dichlorotetrafluoroethane (CClF 2 CClF 2 ), and of (0.6321CHClF 2 + 0.3679CClF 2 CF 3 ), an azeotropic mixture, have been measured. Measurements were carried out with a magnetic densimeter for temperatures from 203 K up to a temperature close to the critical. An accuracy of ±0.1 per cent except for the results at temperatures above 423 K was confirmed by examining the present measurements for orthobaric (liquid + gaseous) water. The temperature dependence of the orthobaric liquid density has been correlated analytically on the basis of the present results and the more reliable of the reported measurements critically evaluated by the present authors.

A gas chromatographic method has been developed for the detection and identification of some volatile organic compounds in whole blood, plasma or serum. After incubation of the sample (200 microliters) together with the internal standard solution in a sealed vial, a portion of the headspace is analysed using a 2-m glass column packed with 0.3% (w/w) Carbowax 20M on Carbopack C, 80-100 mesh. The column oven, after a 2-min isothermal period, is programmed from 35 to 175 degrees C at 5 degrees/min and held for 8 min. The effluent is monitored by both flame-ionisation and electron-capture detection, and peak assignment is by means of retention time and relative detector response. The method has proved applicable to the detection of bromochlorodifluoromethane, n-butane, carbon tetrachloride, chlorobutanol, cryofluorane (Halon 114), dichlorodifluoromethane (Halon 12), ethyl acetate, halothane, isobutane, isopropanol, isopropyl nitrate, methyl ethyl ketone, propane, tetrachloroethylene, toluene, 1,1,1-trichloroethane, 2,2,2-trichloroethanol, trichloroethylene and trichlorofluoromethane (Halon 11) in blood specimens obtained from patients suspected of abusing these agents.

The far-infrared rotational spectra of chlorotrifluoromethane, dichlorodifluoromethane, and trichlorofluoromethane have been observed with an interferometric (Fourier transform) spectrometer in the region 10–40 cm −1 at a resolution of 0.07 cm −1 . CCl 2 F 2 exhibits a continuum spectrum at this resolution, but symmetric top rotational fine structure is observed for CClF 3 and CCl 3 F. Isotope splitting is also observed in CClF 3 , and analysis yields the rotational constants for C 35 ClF 3 of B 0 = 0.11112 cm −1 , D J = 1.6 × 10 −8 cm −1 ; and for C 37 ClF 3 , B 0 = 0.10835 cm −1 , D J = 1.5 · 10 −8 cm −1 . Isotopic shifts can be allowed for in CCl 3 F to yield constants for C 35 Cl 3 F of B 0 = 0.0821 cm −1 , D J = 1 × 10 −8 cm −1 . These values are all in agreement with those deduced from microwave studies of the low J transitions apart from B 0 for C 35 ClF 3 , where the difference is outside the expected experimental error.

Organic fluorine comounds are widely used for working fluid in industry. Applications and practical examples are described in regard of trichlorofluoromethane (F-11), 1, 2-dichlorotetrafluoroethane (F-114), 1, 1, 2 -trichlorotrifluoroethane (F-113), 2, 2, 2-trifluoroethanol (CF3CH2OH), bromotrifluoromethane (CF3Br), trifluoromethane (F-23) and dichlorodifluoromethane (F-12).

By means of the capillary rise method, we have measured the surface tension of four different kinds of halogenated hydrocarbons, namely, trichlorofluoromethane (CCl3F; R 11), dichlorodifluoromethane (CCl2F2; R 12), trichlorotrifluoroethane (C2Cl3F3; R 113), and dichlorotetrafluorethane (C2Cl2F4; R 114). Under the coexistence of the sample liquid with its saturated vapor in equilibrium, the measurements have been performed within the maximum uncertainty of 0.12 mN · m−1 at temperatures from 273 K up to near the critical point of the respective substances. Under the same experimental conditions, two sets of surface tension data have been obtained with two different Pyrex glass capillaries whose inner radii were 0.1536±0.0004 and 0.1724±0.0005 mm, respectively. The two sets of data were in agreement within 0.1 mN · m−1. The data were represented by van der Waals-type correlations with a standard deviation of 0.10 mN · m−1 for CCl3F, 0.04 mN · m−1 for CCl2F2, 0.08 mN · m−1 for C2Cl3F3, and 0.07 mN · m−1 for C2Cl2F4, respectively.

Donkeys were exposed to trichlorofluoromethane (FC11), dichlorodifluoromethane (FC12) and an equivolume mixture of the two to determine their effects on tracheobronchial particle deposition and mucociliary clearance. There was no statistically significant evidence of changes beyond those variations observed in corresponding air control tests.

The reactivity of dichlorodifluoromethane, trichlorofluoromethane, dichlorofluoromethane, chlorodifluoromethane, bromotrifluoromethane, and trichlorotrifluoroethane on a 13X Davison molecular sieve at temperatures of 150 and 320 °C has been examined. For each of these, the nature and concentration of the resulting products have been determined, the variation of sorption capacity of the sieve for carbon dioxide has been measured, and the amount of acid products resulting from sweeping by means of nitrogen saturated with water vapor has been estimated. All the halogenomethanes decompose at 320 °C and only trichlorotrifluoroethane and bromotrifluoromethane do not decompose at 150 °C. The main destruction product is always carbon dioxide, except for dichlorofluoromethane and chlorodifluoromethane which give carbon monoxide. When decomposition is extensive, it gives rise to strong acids during the reaction and during sweeping by means of nitrogen saturated with water vapor. The toxics seen are carbon monoxide and phosgene. Sorption capacity is strongly decreased and is not entirely recovered after sweeping by means of nitrogen saturated with water vapor.

A method for the determination of fron-11 (trichlorofluoromethane), 12 (dichlorodifluoromethane), 113 (1, 1, 2-trichloro-1, 2, 2-trifluoroethane) and 114 (1, 2-dichloro-1, 1, 2, 2-tetrafluoroethane) in household aerosol products by gas chromatography was developed. For the determination of fron-11, 12 and 114, a disposable polyethylene bag was used as a sampling bag. Propelling the aerosol products in the sampling bag, the bag was warmed to vaporize fron-11, 12 and 114. The gaseous volume of the bag was measured with 1.3 l syringe and 1 ml of the gas injected to a gas chromatograph equipped with a thermal conductivity detector. In this gas chromatography, nitrogen gas was used as a carrier gas to detect only fron-species as positive peaks, while other gases as negative peaks. For the determination of fron-113, sample liquid was collected in a 100 ml beaker by propelling the aerosol products. To 1.0g of sample liquid, 1 ml of 10% bromodichloromethane hexane solution was added as an internal standard and made up to 100 ml with ethanol. One ml of the solution was diluted to 100 ml with hexane, and 1 ml of them was passed through Sep-pak [○!R] and made up to 50 ml with hexane. Five μl of the solution was injected to a gas chromatograph equipped with an electron capture detector. Recovery tests for fron-11, 12 and 114 were 87.4-104.9%, and that for fron-113 was 94.9-96.9%. By this method, 154 commercial aerosol products were analyzed, and 0.4-100.0% (w/w) of frons were determined in 45 products.

The solubilities of trichlorofluoromethane (F-11) and dichlorodifluoromethane (F-12) were determined in seawater (35 × 10 −3 ) and in distilled water from 0 to 30°C. Aqueous concentrations were determined by GC-EC subsequent to equilibration with clean, ambient air containing approximately 200 ppt(v) F-11 and 340 ppt(v) F-12. Our compressed air standard was independently calibrated and we estimate the accuracy and precision of the measurement to be approximately 2%. The temperature dependence of the solubility was determined by fitting the observations to the first three terms of the integrated van't Hoff equation at a constant 35 × 10 −3 salinity. A comparison of the extant solubility data in seawater our determinations indicates considerable variability for both F-11 and F-12. Our solubility measurements also are compared to observed concentrations in the surface waters of the eastern, central, and western North Pacific in December 1980, July 1981, June 1982, and March and April 1983, and suggest a supersaturation of 1 to 2% for both fluorocarbons with little or no temperature bias in the surface North Pacific.

The halogenated aliphatic hydrocarbons represent one of the most important categories of industrial chemicals from a consideration of volume, use categories, environmental and toxicological considerations and hence most importantly, potential population risk. The major halocarbons reviewed, primarily in terms of their occurrence, utility, stability, distribution, and levels of exposure as well as their metabolism, carcinogenicity and mutagenicity included: vinylchloride, vinylidene chloride, trichloroethylene, perchloroethylene, ethylene dichloride, ethylene dibromide, chloroprene, chloroform, carbon tetrachloride, fluorocarbons (trichlorofluoromethane and dichlorodifluoromethane), epichlorohydrin, halohydrins (2-chloro- and 2-bromoethanol) and haloethers ( bis (chloromethyl); chloromethyl'-methyl; bis (2-chloroethyl)- and bis (2-chloroisopropyl)ether. In many instances, data were not available to assess world production, populations at risk and degrees of exposure. With the exception of vinylchloride, vinylidene chloride, epichlorohydrin and 2-halo ethanols, there is an acknowledged paucity of definitive mutagenicity data concerning the majority of halogenated hydrocarbons. Their ubiquitous distribution, and in a number of cases, their carcinogenicity both in man and animals, dictates the urgent need to more exhaustively investigate their potential mutagenicity.

The possible biotransformation of trichlorofluoromethane (FC-11) and dichlorodifluoromethane (FC-12) was investigated in 4 male and 2 female adult Beagles after a short (6- to 20-min) inhalation. Dogs were anesthetized with ketamine and succinylcholine, intubated, and ventilated artificially. Trichlorofluoromethane (1000–5000 ppm, v v ) or dichlorodifluoromethane 38000–12,000 ppm, v v ) containing up to 180μ Ci of [ 14 C ] fluorocarbon was delivered from 110-liter Teflon bags, and all exhalations were collected via a nonrebreathing valve in similar bags for 1 hr. Venous blood samples were withdrawn at appropriate times and assayed for fluorocarbon-associated radioactivity. Exhalation bags were assayed for [ 14 C ] fluorocarbon and 14CO2. Urine was collected for up to 3 days and assayed for 14 C metabolites as nonvolatile radioactivity. In some experiments animals were sacrificed 24 hr after exposure and tissues were removed for determination of nonvolatile radioactivity. Essentially all of the administered (inhaled) fluorocarbon was recovered in the exhaled air within 1 hr. Only traces of radioactivity were found in urine or exhaled carbon dioxide. All tissues contained measurable concentrations of nonvolatile radioactivity 24 hr after exposure but together represented less than 1% of the administered dose. It is not possible to determine if these trace levels are associated with metabolites of the fluorocarbons or with the unavoidable radiolabeled impurities present in the administered gas mixture. Neither phenobarbital pretreatment (60 mg/day for 3 days) nor prolonged exposure (50–90 min) produced any alteration of these results. Thus, it can be concluded that FC-11 and FC-12 are relatively refractory to biotransformation after a short inhalation exposure and that they are rapidly exhaled in their unaltered chemical form.

This report describes the death of a teenager due to inhalation of fluorocarbon aerosol propellants and presents a method for the determination of trichlorofluoromethane (fluorocarbon 11) and dichlorodifluoromethane (fluorocarbon 12) in post-mortem samples. The post-mortem blood and tissue levels of these fluorocarbons are also presented. The distribution of fluorocarbon 11 and fluorocarbon 12 is similar to that observed in chloroform deaths.

Water samples from the central and eastern basins of Lake Erie were analyzed for volatile chloro- and chlorofluorocarbons for a one-week period in each of 1977 and 1978. The following contaminants were observed with mean concentrations and standard deviations in 1978 with the corresponding values for 1977 in parentheses: Dichlorodifluoromethane (Freon 12) 76±38 (73±36) ng°L−1; trichlorofluoromethane (Freon 11) 34±26 (46±40) ng·L−1; chloroform 15±4 ng·L−1; carbon tetrachloride 19±11 (37±20) ng·LT−1; trichloroethylene 20±13 (11±9) ng·L−1. Except for carbon tetrachloride and trichloroethylene, the distribution patterns appear to show little correlation with each other. Chloroform concentrations were relatively uniform, however the carbon tetrachloride and trichloroethylene concentrations appear to be point-source related with discharges along the south shore of Lake Erie. Freon 12 concentrations were generally higher in the eastern basin than in the central basin, while Freon 11 levels were high and relatively uniform throughout the study area.

Fluorine- 18 recoil labelling of trichlorofluoro-, dichlorodifluoro-, chlorotrifluoro- and tetrafluoromethane has been investigated. Mixtures of an appropriate substrate (0.3–2%) in neon were bombarded with 14 MeV deutrons [20Ne (d, α)18F reaction]. All the above compounds were labelled in high activities by this technique. When tetrachloromethane was the substrate the major product was 18F-trichlorofluoromethane (≈95% of total gaseous activity). Fluorine-18-dichlorodifluoromethane was the major product (≈60 and ≈70% respectively) when either trichlorofluoromethane or dichlorodifluoromethane was the substrate. The use of chlorotrifluoromethane as substrate produced 18F-dichlorodifluoromethane and 18F-tetrafluoromethane in significant amounts in addition to 18F-chlorotrifluoromethane (≈40%). Bombardment of mixtures of tetrafluoromethane in neon produced 18F-tetrafluoromethane (≈80%) together with other 18F-labelled gaseous products. The targetry and irradiation conditions are described. The volatile products were analysed by radio-gas chromatography.

A specific and sensitive method is described for the determination of residual ethylene oxide, dichlorodifluoromethane and trichlorofluoromethane in sterilized plastic surgical equipment. Residues are isolated from the plastics by high vacuum distillation and analysed by gas chromatography using an exponential dilution apparatus, to avoid the use of solvents. Under the conditions specified, a lower limit of 1 ppm of each component could be detected in blood giving sets of which the main plastics material was PVC. The rate of loss of each component has been studied, to indicate the necessary holding time of the material before it can be considered safe to use.

A convenient method for the sampling and total analysis of the propellents and active agents contained in aerosol irritant projectors has been developed. A gas chromatograph equipped with a column packed with 6% Carbowax 20M on Chromosorb G and coupled to a mass spectrometer provides both quantitative and qualitative analysis for the components of a typical irritant projector. The main lachrymator, bromoacetone, represented 1.5% and the propellents dichlorodifluoromethane and trichlorofluoromethane, comprised 97.7% of the aerosol mixture.

Three propellant chlorofluorocarbons, namely trichlorofluoromethane (FC11), dichlorodifluoromethane (FC12), and chlorodifluoromethane (FC22) were administered by inhalation at a concentration of 5000, 1000 and 0 ppm, 4 hours daily, 5 days weekly, for 104 and 78 weeks, to rats and mice, respectively. The animals were kept under observation until spontaneous death. Under the experimental conditions, all three compounds failed to show any carcinogenic effects.