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Introduction: Causeway is providing a road link between travelers from Al-Khobar, Saudi Arabia and Bahrain. The vehicle traffic noise and emissions exhaust at Causeway have a significant effect on air quality parameters which leads to deteriorations impact on health of employees and passengers. The present study aimed to analyze the ambient air pollutants PM10, PM2.5, PM1, O3, CO2, SO2, CO, VOCs, and NO2, ambient noise and heat stress in and around causeway. Materials and Methods: All gaseous, particulate air pollutants, meteorological factors, ambient noise and heat stress were analyzed using standards calibrated equipment. July 2019 to October 2019 the study incused seven administrative sites in King Fahd causeway (Saudi Side). Air Quality Index (AQI) was used to determine the concentrations of selected ambient air pollutants. Results: All major air pollutants were high and significant difference in the concentration level between weekdays and weekends (p<0.05) and exceeds the international air quality guidelines in the selected studied sites of causeways. However, ambient noise demonstrated high significant levels in different studied sites in different times (p<0.05). Conclusion: Air quality measures in Causeway are significantly deteriorated and should be continuously evaluated to minimize the risk of daily exposure to traffic emissions.

Introduction: Exposure to loud noise is a major problem for medical staff, especially in dental clinics and laboratories. Aim: This research aims to assess the ambient noise in dental clinics and the impact of noise on medical staff in dental clinics at Dammam Medical Complex, Saudi Arabia. Materials and Methods: A Cross sectional study was performed. Ambient noise was measured using the sound level meter in various laboratories and clinics. Results: The data showed that the maximum noise levels were between 116 and 56 dB(A) with peak levels ranging from 116 to 106 dB(A) in the laboratory and clinic environment. There is a significant correlation with the number of medical personnel, the area of the laboratory or clinic and the number and nature of the equipment used with the sources and ambient noise in their workplace and with daily exposure might cause severe impact on hearing loss in such clinics. Conclusion: The study strongly recommends the implementation of preventive measures and should be for periodic medical examinations and educational programs of the highest priority for medical staff in clinics and dental laboratories.

Background: Workers working in the steel industry has commonly exposed to heat which lead to health risk. The objective of this study was to assess heat stress among steel production workers. Materials and Methods: It is a cross sectional study, 186 workers were selected through simple random sampling. There are two groups of workers staff and line production. The Wet Bulb Global Temperature (WBGT) index was measured from Heat Stress Monitor (Casella Micro herm WBGT) and Heat Strain Score Index (HSSI). Spearmen correlation for determine the correlation between WBGT and HSSI and association between risk factors and HSSI determined through logistic regression. Results: The mean and SD values of the wet bulb global temperature was 32.46 (2.01) and these values exceed Threshold Limit Values (TLV by American Conference of Governmental Industrial Hygienists (ACGIH) standard and HSSI scores showed that 24.3% of the exposed workers were in red dangerous zone (severe heat strain). The WBGT and HSSI values are positively correlated (r = 0.85) (P = 0.001). Risk factors associated with heat stress after adjustment are age 19-35 years (OR 6.07, CI 1.78-21.90), years of experience >10 years (OR 4.67. CI 1.23-18.42), ever smoking (OR 1.58, CI 1.08-4.57) and overweight (OR 1.56, CI 1.20-12.48). Conclusion: The finding of this study showed that heat stress is common hazard among steel workers and the heat conservation planning intervention action should be conducted to reduce exposure.

Objetivos: Verificar el papel de los riesgos ambientales en el proceso de desarrollo de la leucemia linfoblástica aguda (LLA) en la infancia. Materiales y métodos: Se realizó una búsqueda en la literatura científica con el fin de evaluar el papel de los factores de riesgo ambientales en el desarrollo de la leucemia linfoblástica aguda. Resultados: El papel del medio ambiente en el desarrollo de la lla en niños es desconocida. La teoría de dos etapas propuesta por Greaves, en 1988 es la hipótesis más aceptable. Un primer evento se produce en el útero o cerca del momento del nacimiento; esta mutación induce el desarrollo de clones pre-leucemia. Otro acontecimiento, suceso en la infancia temprana, se desarrollaría este primer clon de pre-leucemia en leucemia clínica. Con base en los eventos ambientales relacionados con otros tipos de leucemia y en otros estudios, algunos factores de riesgo se han propuesto como la inducción de las mutaciones que conducen a lla. Radiación (ionizante o no), agentes infecciosos, y productos químicos se cree que son los responsables de la enfermedad. En las últimas décadas, muchos autores intentaron encontrado una asociación entre estos factores de riesgo y el desarrollo de la LLA infantil. Sin embargo los resultados no fueron concluyentes e incluso contradictorias. La radiación ionizante es el único demostrado desempeñar un papel en el desarrollo de la leucemia. Conclusión: Como la leucemia es una enfermedad que afecta a los niños, los costos de esta patología son altos cuando se habla de dinero gastar para el diagnóstico y tratamiento y cuando se piensa en la carga social y psicológico. Teniendo en cuenta la teoría propuesta por Greaves, hay por lo menos dos momentos cuando el paciente debe evitar la exposición que conduce a la leucemia. Por lo tanto, es muy importante encontrar el factor de riesgo real, o factores, que están involucrados en el proceso., Objectives: To verify the paper of environmental risks in the process of developing Acute lymphoblastic leukemia (ALL) in childhood. Materials and methods: A search was conducted on scientific literature in order to evaluate the role of environmental risk factors in acute lymphoblastic leukemia development. Results: The environmental role in development of all in children is unknown. The two steps theory proposed by Greaves in 1988 is the most acceptable hypothesis. One first event occurs in uterus or near the moment of birth; this mutation induces the development of pre-leukemia clones. Another event, happening in the early infancy, would develop this rst pre-leukemia clone into clinical leukemia. Based on the environmental events linked to other types of leukemia and in other studies, some risk factors have been proposed as inducing the mutations leading to all. Radiation (ionizing or not), infectious agents, and chemical products are thought to be the responsible for the disease. In the last decades, many authors tried to found an association between these risk factors and the development of childhood ALL. The results however were inconclusive and even contradictories. Ionizing radiation is the only one proved to play a role in the development of leukemia. Conclusion: As leukemia is a disease that affects children, costs of this pathology are high when talking about money expend for diagnosis and treatment and when thinking on the social and psychological burden. Considering the theory proposed by Greaves, there are at least, two moments, when the patient should avoid the exposition that leads to leukemia. Therefore, it is very important to nd the real risk factor or factors that are involved in the process., Objetivos: Para veri car o papel dos riscos ambientais no processo de desenvolvimento da leucemia linfoblástica aguda (LLA) na infância. Materiais e métodos: realizou-se uma busca na literatura científica com o fim de avaliar o papel dos fatores de risco ambientais no desenvolvimento da leucemia linfoblástica aguda. Resultados: O papel do meio ambiente no desenvolvimento da LLA em crianças é desconhecido. A teoria de duas etapas proposto por Greaves, em 1988 é a hipótese mais aceitável. Um primeiro evento se produz “no útero” ou perto do momento do nascimento; esta mutação induz o desenvolvimento de clones pré-leucemia. Outro acontecimento, sucedido na infância precoce, se desenvolveria este primeiro clone de pré-leucemia em leucemia clínica. Com base nos eventos ambientais relacionados com outros tipos de leucemia e em outros estudos, alguns fatores de risco se têm proposto como a indução das mutações que conduzem a LLA infantil. Radiação (ionizante ou não), agentes infecciosos, e produtos químicos acredita-se que são responsáveis da doença. Nas últimas décadas, muitos autores tentaram encontrar uma associação entre estes fatores de risco e o desenvolvimento da LLA infantil. No entanto, os resultados não foram concludentes e inclusive contraditórios. A radiação ionizante é o único demonstrado desempenhar um papel no desenvolvimento da leucemia. Conclusão: Como a leucemia é uma doença que afeta às crianças, os custos desta patologia são altos quando se fala de dinheiro gasto para o diagnóstico e tratamento, e quando se pensa na carga social e psicológica. Tendo em conta a teoria proposta por Greaves, há pelo menos dois momentos quando o paciente deve evitar a exposição que conduz à leucemia. Pelo tanto, é muito importante encontrar o fator de risco real, ou fatores, que estão envolvidos no processo.

Immigrant populations provide a unique intersection of cultural and environmental risk factors implicated in asthma etiology. This study focuses on asthma prevalence and severity in 600 Arab American households in metro Detroit, the largest immigrant reception zone for Arab Americans in North America. The survey method introduced a number of novel features: (a) a ranking scheme for the key environmental risk factors for asthma was used to derive an aggregated environmental risk index (ERI) for each household, and (b) an aggregate measure of asthma severity based on symptom frequency and intensity. Environmental risk factors and surrogates for socioeconomic status (SES) were found to be stronger predictors of asthma prevalence than asthma severity, while demographic variables such as English fluency and birth in the United States were better predictors of asthma severity than asthma prevalence. These results suggest that SES variables may be more reflective of environmental exposures in communities involved in this study, while English fluency and birth in the United States may be linked to health care access and utilization behavior that can influence the asthma management. We also found a significant relationship between asthma prevalence and degree of acculturation. Asthma prevalence was highest among moderately acculturated immigrants compared with new immigrants and those who were well acculturated, suggesting that among Arab Americans in the Detroit area, risk factors associated with new immigrant status are replaced by???western??? risk factors as the population becomes more acculturated.

Background The Health and Safety Department of the United Automobile Workers recently introduced the use of Advanced Training Technologies (ATTs) into a previously successful Industrial Emergency Response (IER) program. The new curriculum attempted to incorporate web-based technology, while preserving the historical emphasis on the use of peer trainers and the Small Group Activity Method (SGAM) to promote team problem solving and worker empowerment. Methods The University of Michigan evaluated the program by administering a survey combining open- and closed-ended questions to trainees. Results Of the 46 respondents, most rated the program very highly, found that the use of internet technology allowed faster access to current information, reported peer trainers as one of program aspects they liked best, and did not find working in groups of three per computer difficult. Conclusions It is possible to enhance a workplace health and safety training program through the introduction of ATT without compromising participant-centered, group learning program philosophies. Am. J. Ind. Med. 43:429-435, 2003. © 2003 Wiley-Liss, Inc.

Background The long-term impact of the United Automobile Workers' (UAW) Industrial Emergency Response Training on health and safety conditions and practices in plants is described. Two strategies are combined in this 24-hour training: the use of peer (worker) trainers and a participant-centered approach, the Small Group Activity Method (SGAM). Methods Impact was assessed through a telephone survey of 67 trainees conducted on average 16.8 months post-training. Results 74% of trainees reported using at least one of the provided written training materials after training. Of those reporting an accident in their facility after training, 88% said it was handled differently because of training. Trainees report that peer-trainers are more knowledgeable and communicate better than do other types of trainers. Trainees also reported that SGAM made training more applicable to their workplace. 98.5% of trainees like the methods utilized. Conclusions Worker-trainers and SGAM are effective training methods enhancing the long-term impact of union-based workplace health and safety training programs. Am. J. Ind. Med. 38:598-605, 2000. © 2000 Wiley-Liss, Inc.

Exposure to metalworking fluids has been linked to modest cross-shift reductions in FEV 1 and occupational asthma. To identify responsible agents, we measured personal exposures to thoracic particulate (TP), viable plus nonviable thoracic bacteria (BAC), and vapor phase nicotine (VPN) (as a surrogate for tobacco particulate) among 83 machinists exposed to soluble oils and 46 dry assemblers working in an automotive transmission machining plant using biocides infrequently. The participants completed interviews and performed pre- and postshift spirometry on Monday and Thursday of the same week in each of three rounds of data collection (June 1992, January 1993, June 1993). Generalized estimating equations were used to combine information across rounds in multiple regression models of cross-shift and cross-week changes in forced expiratory volume, I second (FEV 1) and forced vital capacity (FVC). Mean seniority was 19 years among machinists. Mean personal TP levels were 0.41 mg/m 3 in machinists and 0.13 mg/m 3 in assemblers. Six of the 83 machinists and none of the 46 assemblers experienced a greater than 19% cross-shift decrement in FEV 1 or FVC at least once (p = .07). In regression models using either TP or BAC, among subjects with lower baseline (Monday preshift) FEV 1 /FVC ratios, increasing exposure was significantly associated with increasing cross-shift decrements in FEV 1 and FVC in linear models, and with increased likelihood of a 10% or greater cross-shift decrement in FEV 1 or FVC in logistic models. Adjustment of TP for VPN did not affect models significantly. We conclude that clinically important cross-shift decrements in pulmonary function are associated with exposure to metalworking fluid aerosols within a high-seniority population. Am. J. Ind. Med. 31:510-524, 1997. © 1997 Wiley-Liss, Inc.

Introduction: The correlation between monofilament testing, symptom surveys, and electrodiagnostic studies for the diagnosis of axonal polyneuropathy has not been well studied. This investigation was done to assess the agreement between these procedures in a non???random sample of volunteers. Methods: The procedures evaluated included electrodiagnostic tests of the sural nerve, monofilament testing of the great toe, a symptom survey, and a body diagram. Kappa coefficients and sensitivity and specificity, using nerve conduction as a ???gold standard,??? were used to determine the agreement between various combinations of procedures. Results: Poor agreement (kappa values ???0.12???0.44) and sensitivity (sensitivity <30%) were found for all combinations of symptoms and monofilament results in comparison with sural peak latency and amplitude. Conclusions: Overall, the results demonstrated a low discriminatory power for the screening procedures for identifying persons with impaired sural nerve function. The results highlight the need for further development and evaluation of screening methods for distal neuropathy in population???based studies. Muscle Nerve, 2012

Introduction: Nerve conduction velocity slows and amplitude declines with aging. Methods: Median and ulnar sensory nerves were tested at the annual meetings of the American Dental Association. Seven hundred four subjects had at least two observations. The rate of change in the nerve parameters was estimated while controlling for gender, age, change in hand temperature, baseline body mass index (BMI), and change in BMI. Results: Amplitudes of the median sensory nerve action potentials decreased by 0.58 ??V per year, whereas conduction velocity decreased at a rate of 0.41 m/s per year. Corresponding values for the ulnar nerve were 0.89 ??V and 0.29 m/s per year. The rates of change in amplitudes did not differ, but the median nerve demonstrated a more rapid loss of conduction velocity. Conclusions: The rate of change for the median conduction velocity was higher than previously reported. The rate of change of median conduction velocity was significantly greater than for the ulnar nerve. Muscle Nerve 45: 60???64, 2012

Recently, we reported that mutations in the neuropathy target esterase (NTE) gene cause autosomal recessive motor neuron disease (NTE-MND). We describe clinical, neurophysiologic, and neuroimaging features of affected subjects in the index families. NTE-MND subjects exhibited progressive lower extremity spastic weakness that began in childhood and was later associated with atrophy of distal leg and intrinsic hand muscles. NTE-MND resembles Troyer syndrome, except that short stature, cognitive impairment, and dysmorphic features, which often accompany Troyer syndrome, are not features of NTE-MND. Early onset, symmetry, and slow progression distinguish NTE-MND from typical amyotrophic lateral sclerosis. NTE is implicated in organophosphorus compound???induced delayed neurotoxicity (OPIDN). NTE-MND patients have upper and lower motor neuron deficits that are similar to OPIDN. Motor neuron degeneration in subjects with NTE mutations supports the role of NTE and its biochemical cascade in the molecular pathogenesis of OPIDN and possibly other degenerative neurologic disorders. Muscle Nerve, 2011

Background Physical examination is often used to screen workers for carpal tunnel syndrome (CTS). In a population of newly hired workers, we evaluated the yield of such screening. Methods Our study population included 1,108 newly hired workers in diverse industries. Baseline data included a symptom questionnaire, physical exam, and bilateral nerve conduction testing of the median and ulnar nerves; individual results were not shared with the employer. We tested three outcomes: symptoms of CTS, abnormal median nerve conduction, and a case definition of CTS that required both symptoms and median neuropathy. Results Of the exam measures used, only Semmes???Weinstein sensory testing had a sensitivity value above 31%. Positive predictive values were low, and likelihood ratios were all under 5.0 for positive testing and over 0.2 for negative testing. Conclusion Physical examination maneuvers have a low yield for the diagnosis of CTS in workplace surveillance programs and in post-offer, pre-placement screening programs. Am. J. Ind. Med. 54:1???9, 2011. ?? 2010 Wiley-Liss, Inc.

The University of Michigan Dioxin Exposure Study was undertaken to address concerns that the industrial discharge of dioxin-like compounds in the Midland, Michigan, USA area had resulted in the contamination of soil and vegetation in the Tittabawassee River floodplain and downwind of the incinerator in the City of Midland. The study included the analysis of 597 vegetation samples, predominantly grass and weeds, from residential properties selected through a multistage probabilistic sample design in the Midland area, and in Jackson and Calhoun Counties (Michigan), as a background comparison, for 29 polychlorinated dibenzo- p -dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs). The mean toxic equivalent (TEQ) of the house perimeter vegetation samples ranged from 4.2 to 377???pg/g. The ratio of TEQs (vegetation to soil) was about 0.3, with a maximum of 3.5. Based on a calculation of the similarity of the congener patterns between the soil and the vegetation, it appeared that the source of the contamination on the vegetation was the surrounding soil. This conclusion was supported by linear regression analysis, which showed that the largest contributor to the R 2 for the outcome variable of log 10 of the vegetation concentration was log 10 of the surrounding soil concentration. Models of vegetation contamination usually focus on atmospheric deposition and partitioning. The results obtained here suggest that the deposition of soil particles onto vegetation is a significant route of contamination for residential herbage. Thus, the inclusion of deposition of soil particles onto vegetation is critical to the accurate modeling of contamination residential herbage in communities impacted by historic industrial discharges of persistent organic compounds. Environ. Toxicol. Chem. 2010;29:2660???2668. ?? 2010 SETAC

Tobacco smoke and its metabolites are carcinogens that increase tissue oxidative stress and induce target tissue inflammation. We hypothesized that genetic variation of inflammatory pathway genes plays a role in tobacco-related carcinogenesis and is modified by tobacco smoking. We evaluated the association of 12 single nucleotide polymorphisms of 8 inflammation-related genes with tobacco-related cancers (lung, oropharynx, larynx, esophagus, stomach, liver, bladder, and kidney) using 3 case-control studies from: Los Angeles (population-based; 611 lung and 553 upper aero-digestive tract cancer cases and 1,040 controls), Taixing, China (population-based; 218 esophagus, 206 stomach, 204 liver cancer cases, and 415 controls), and Memorial Sloan-Kettering Cancer Center (hospital-based; 227 bladder cancer cases and 211 controls). After adjusting for age, education, ethnicity, gender, and tobacco smoking, IL10 rs1800871 was inversely associated with oropharyngeal cancer (CT+TT vs . CC adjusted odds ratio [aOR]: 0.69, 95% confidence interval [CI]: 0.50???0.95), and was positively associated with lung cancer among never smokers (TT vs . CT+CC aOR: 2.5, 95% CI: 1.3???5.1) and inversely with oropharyngeal cancer among ever smokers (CT+TT vs . CC aOR: 0.63, 95% CI: 0.41???0.95). Among all pooled never smokers (588 cases and 816 controls), TNF rs1799964 was inversely associated with smoking-related cancer (CC vs . CT+TT aOR: 0.36, 95% CI: 0.17???0.77). Bayesian correction for multiple comparisons suggests that chance is unlikely to explain our findings (although epigenetic mechanisms may be in effect), which support our hypotheses, suggesting that IL10 rs1800871 is a susceptibility marker for oropharyngeal and lung cancers, and that TNF rs1799964 is associated with smoking-related cancers among never smokers.

Providing adequate sanitation facilities to the poor is a major challenge facing developing nations such as South Africa. Increasing population pressure adds to the problem of providing sanitation in many of these countries, especially in urban areas. As a result of increased pressure on infrastructure there has been a disturbing increase in the number of poorly designed and poorly operated waterborne sewerage systems, especially in densely populated settlements in South Africa. When sanitation fails or is inadequate the impact on the health of the community and on the receiving water environment can be extremely serious. The population issue and urbanisation have placed pressure on local authorities to provide adequate sanitation facilities, and just as importantly, educating people using these facilities regarding proper maintenance and use of these facilities. The study is aimed to determine how and why the sanitation and water related practices or behaviour of Poding Tse Rolo community contributes to the sewer and manhole blockages. This community was chosen because the Department of Water Affairs and Forestry (DWAF) Free State region received several complaints of sanitation problems from the community members such as farmers, and individual members who are directly affected by the wastewater overflows in this area. Through discussions with some of the community members and municipal officials an interest was expressed in finding possible solutions to the above problem. The majority of people in Poding Tse Rolo are using waterborne systems that are situated in-yard (not in-house) with only a small portion of the township, still using bucket systems. The samples collected indicated that 42 percent of the breadwinners in Poding Tse Rolo are domestic workers with only 25 percent working as general workers or in government departments. Manhole blockages are due to foreign objects such as spoons, cloths and plastics. Although the findings indicated that households r

Objectives : This study, the first to document the prevalence of pneumoconiosis among a living South African coal mining cohort, describes dose???response relationships between coal workers??? pneumoconiosis and respirable dust exposure, and relationships between pneumoconiosis and both lung function deterioration and respiratory symptoms. Methods : A total of 684 current miners and 188 ex-miners from three bituminous-coal mines in Mpumalanga, South Africa, was studied. Chest radiographs were read according to the International Labour Organization (ILO) classification by two experienced readers, one an accredited National Institute for Occupational Safety and Health (NIOSH)???B??? reader. Interviews were conducted to assess symptoms, work histories (also obtained from company records), smoking, and other risk factors. Spirometry was performed by trained technicians. Cumulative respirable dust exposure (CDE) estimates were constructed from historical company-collected sampling and researcher-collected personal dust measurements.??-Statistics compared the radiographic outcomes predicted by the two readers. An average profusion score was used in the analysis for the outcomes of interest. Because of possible confounding by employment status, most analyses were stratified on current and ex-miner status. Results : The overall prevalence of pneumoconiosis was low (2%???4%). The degree of agreement between the two readers for profusion was moderate to high (??=0.58). A significant association (P <0.001) and trend (P <0.001) was seen for pneumoconiosis with increasing categories of CDE among current miners only. A significant (P <0.0001) additional 58??mg-years/m 3 CDE was seen among those with pneumoconiosis compared to those without. CDE contributed to a statistically significant 0.19% and 0.11% greater decline in the percent predicted 1-second forced expiration volume (FEV 1) and forced vital capacity (FVC), respectively, among current miners with pneumoconiosis tha

Invasion of zebra mussels, Dreissena polymorpha, and round gobies, Neogobius melanostomus, into the Great Lakes has altered the food web structure and thereby the pathways of toxic contaminants such as polychlorinated biphenyls (PCBs) and polychlorinated naphthalenes (PCNs). In this study, concentrations of PCNs and PCBs were measured in organisms of a Great Lakes benthic food chain encompassing zebra mussels. PCNs were found in all of the benthic organisms, including phytoplankton, algae, amphipods, zebra mussels, round goby, and smallmouth bass, Micropterus dolomieui. Concentrations of PCNs were greater in samples collected from the Raisin River than in samples from the St. Clair River. Biomagnification factors (BMF) for tetra- through octa-CN congeners in going from algae to zebra mussels from the St. Clair River ranged from 3 to 10. No major biomagnification of PCNs was found in round gobies, when concentrations were related to those in their prey species, zebra mussels. The biomagnification potential of PCNs appears to be similar to that of PCBs in the benthic food chain investigated in this study, despite the fact that PCNs may be metabolized by organisms higher in the food chain. Among several congeners, the BMFs of PCN congeners 35, 42, 43/45, 52/60, 58, and 66/67 were highest in round gobies. PCNs accounted for 1???22% of the total TEQs (toxic equivalents) of PCBs and PCNs in benthic organisms analyzed in this study. PCB congener 126 was the major contributor to TEQs, accounting for 72???99% of the PCB-TEQs in the food chain organisms analyzed. Correspondence to: K. Kannan, Wadsworth Center, New York State Department of Health, Empire State Plaza, P.O. Box 509, Albany, NY 12201-0509, USA; email: kkannan@wadsworth.org -->

A thorough assessment of human exposure to environmental agents should incorporate mobility patterns and temporal changes in human behaviors and concentrations of contaminants; yet the temporal dimension is often under-emphasized in exposure assessment endeavors, due in part to insufficient tools for visualizing and examining temporal datasets. Spatio-temporal visualization tools are valuable for integrating a temporal component, thus allowing for examination of continuous exposure histories in environmental epidemiologic investigations. An application of these tools to a bladder cancer case-control study in Michigan illustrates continuous exposure life-lines and maps that display smooth, continuous changes over time. Preliminary results suggest increased risk of bladder cancer from combined exposure to arsenic in drinking water (>25 ?? g/day) and heavy smoking (>30 cigarettes/day) in the 1970s and 1980s, and a possible cancer cluster around automotive, paint, and organic chemical industries in the early 1970s. These tools have broad application for examining spatially- and temporally-specific relationships between exposures to environmental risk factors and disease.

No abstract available.

Trophic transfer of perfluorooctanesulfonate (PFOS) and other related perfluorinated compounds was examined in a Great Lakes benthic foodweb including water???algae???zebra mussel???round goby???smallmouth bass. In addition, perfluorinated compounds were measured in livers and eggs of Chinook salmon and lake whitefish, in muscle tissue of carp, and in eggs of brown trout collected from Michigan. Similarly, green frog livers, snapping turtle plasma, mink livers, and bald eagle tissues were analyzed to determine concentrations in higher trophic-level organisms in the food chain. PFOS was the most widely detected compound in benthic organisms at various trophic levels. Concentrations of PFOS in benthic invertebrates such as amphipods and zebra mussels were approximately 1000-fold greater than those in surrounding water, which suggested a bioconcentration factor (BCF; concentration in biota/concentration in water) of 1000 in benthic invertebrates. Concentrations of PFOS in round gobies were two- to fourfold greater than those in their prey organisms such as zebra mussels and amphipods. Concentrations of PFOS in predatory fishes (Chinook salmon and lake whitefish) were 10 to 20-fold greater than those in their prey species. Concentrations of PFOS in mink and bald eagles were, on average, 5- to 10-fold greater than those in Chinook salmon, carp, or snapping turtles. Because of the accumulation of PFOS in liver and blood, the biomagnification factor (BMF) of perfluorinated compounds in higher trophic-level organisms such as salmonid fishes, mink, and eagles were based on the concentrations in livers or plasma. Overall, these results suggest a BCF of PFOS of approximately 1000 (whole-body based) in benthic invertebrates, and a BMF of 10 to 20 in mink or bald eagles, relative to their prey items. Eggs of fish contained notable concentrations of PFOS, suggesting oviparous transfer of this compound. PFOA was found in water, but its biomagnification potential was lower than tha

Histone deacetylase inhibitors, such as phenylbutyrate, are currently undergoing clinical trials as potential anticancer agents. Phenylbutyrate can induce cell differentiation and apoptosis in a number of cancer cell types and can act in synergy with ionizing radiation and chemotherapy to induce apoptosis. We used the sea urchin embryo basement membrane invasion assay to show that phenylbutyrate potently inhibited the invasive properties of both prostate and breast cancer cells at clinically achievable doses. This inhibition was dose-dependent and persisted for at least 24 hr after the drug was removed. These results suggest that in addition to activating apoptosis in cancer cells, phenylbutyrate may be used in prevention of metastatic disease. © 2002 Wiley-Liss, Inc.

This paper describes ecological investigations performed in an outdoor experimental channel receiving Huron River water and beet sugar or crude molasses during two summers of operation (1965 and 1966). The channel was assembled in two lengths, 645 ft (1965) and 704 ft (1966), with sampling stations located one near the beginning, one in the middle and one near the end. At each station, three strands of knitting yarn were suspended and allowed to remain for 24 hr. After this time, the strands were removed, together with attached growth, and fresh strings replaced. The replicate strings were cut into 10 cm sections, with one-half of these sections used for dry weight determinations. The attached organisms were removed by violently shaking the strings suspended in a measured quantity of water. One drop was then removed and direct microscopic counts and identification made immediately. Dry weights were obtained by drying the strings in aluminum weighing pans overnight at 90[deg]C.A total of 12 experiments was run, the duration of each being in most cases five days. In the first series of experiments flow through the channel was at 100 g/min. at an essentially uniform velocity of 1 ft/sec. Nutrient concentration was varied from 1 mg/l as sucrose. In the last series of experiments, nutrient concentration was held at 5 mg/l and velocity varied at the three stations by altering the height of an overflow weir between 0.0 and 0.6 ft, and changing the flow between 25 and 200 g/min. This provided a range of velocities at the station from 0.09 to 1.49 ft/sec. The results of attached organism determinations are presented following each experiment and their response to nutrient concentration and velocity summarized in the Discussion. Sphaerotilus-dominated biological flocs were stimulated to bloom proportions within 30 hr after the addition of as little as 1 mg/l of sucrose. Maximum growth was obtained at a concentration of 5 mg/l at velocities from 0.58 to 1.49 ft/sec in the temperatur

The environmental contaminant, trimethyltin (TMT), produces a profound elevation in tone intensity necessary to inhibit the acoustic startle reflex in laboratory animals which recovers over a prolonged period except at very high frequencies. The recovery that is observed does not begin until 3 to 5 weeks after a single acute administration depending upon dosage. As opposed to the very temporary threshold shifts by the salicylates and loop diuretics or the permanent and progressive ototoxicity resulting from aminoglycoside antibiotics the time course for recovery of acoustic startle reflex inhibition after TMT appears to be an anomaly for a chemical ototoxicant. In terms of the duration of loss only, this pattern appears similar to that sometimes observed after noise exposure. The current investigation replicates the finding that recovery of acoustic startle reflex inhibition after TMT is frequency related in that only the highest frequency impairment appears to be permanent. While this frequency dependence suggests a cochlear locus of injury, both the known neurotoxic effects of TMT and the time course of the behavioral impairment suggest a more central locus of injury. Compound action potential and cochlear microphonic recordings made from the round window in the current study confirm a preferential high frequency effect of TMT and demonstrate a significant cochlear component to the ototoxic effects of this agent. ototoxicity, peripheral auditory damage, trimethyltin, reflex modification audiometry, compound action potential, cochlear microphonic

Table of contents: Introduction - Well owner responsibilities - Well construction and well maintenance - Water quality protection - Water quality sampling and treatment - Resource guide., California Revealed

90-6SS, The present study was conducted for four consecutive years to assess the exposure of field workers applying herbicide mixtures (2,4-D + Roundup and Garlon 3A + Roundup) and to determine the toxicity and fate of these herbicides in the environment. Study results indicated that exposure of workers to these mixtures via inhalation was insignificant compared to threshold limit values (TLVs) set by the American Conference of Governmental Industrial Hygienists (ACGIH, the National Institute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration (OSHA) for the protection of human health. In addition, herbicide concentrations in the urine of these workers were much higher than those found in air samples collected from breathing zones. This was probably due to exposure via ingestion (eating without proper hand washing) and/or exposure via dermal contact. The analysis of samples taken from the environment including sediment and water collected over three years indicated that 2,4-D, Roundup and Garlon-3A did not pose an immediate (acute) risk to aquatic life in water bodies adjacent to herbicide treated areas on the right-of-way. Moreover, fish, crawfish and microbial acute bioassay results showed that harmful concentrations were not likely to occur as a result of herbicide use under current application rates recommended by the manufacturers.