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Purpose: While CO capture and storage (CCS) technology has been well studied in terms of its efficacy and cost of implementation, there is limited available data concerning the potential for occupational exposure to amines, mixtures of amines, or degradation of by-products from the CCS process. This paper is a critical review of the available data concerning the potential effects of amines and CCS-degradation by-products. Methods: A comprehensive review of the occupational health and safety issues associated with exposure to amines and amine by-products at CCS facilities was performed, along with a review of the regulatory status and guidelines of amines, by-products, and CCS process vapor mixtures. Results: There are no specific guidelines or regulations regarding permissible levels of exposure via air for amines and degradation products that could form atmospheric oxidation of amines released from post-combustion CO capture plants. While there has been a worldwide effort to develop legal and regulatory frameworks for CCS, none are directly related to occupational exposures. Conclusions: By-products of alkanolamine degradation may pose the most significant health hazard to workers in CCS facilities, with several aldehydes, amides, nitramines, and nitrosamines classified as either known or potential/possible human carcinogens. The absence of large-scale CCS facilities; absence and unreliability of reported data in the literature from pilot facilities; and proprietary amine blends make it difficult to estimate potential amine exposures and predict formation and exposure to degradation products. [ABSTRACT FROM AUTHOR]

Objectives: To revise the criteria used in the present “Required Sweat Rate” standard ISO 7933 (1989) for the prediction of the maximum duration of work in hot environments. Methods: Review of the literature and in particular, of the bases for the present criteria. Results: A new method is proposed, to take into account the increase in core temperature associated with activity in neutral environments. The prediction of maximum wetness and maximum sweat rates are revised, as well as the limits for maximum water loss and core temperature. Conclusion: An improved set of maximum values and limits is described, to be used in the revised version of the ISO 7933 standard. Due to the major modifications to the “Required Sweat Rate” index and in order to avoid any confusion, it is suggested that the revised model be renamed the “Predicted Heat Strain” (PHS) model. [ABSTRACT FROM AUTHOR]

The complex of vascular, neurologic, and osteoarticular disorders occurring in the upper limbs of vibration-exposed workers is called hand-arm vibration syndrome. There is epidemiologic evidence for an increased occurrence of peripheral sensorineural disorders in occupational groups working with vibrating tools. An excess risk for wrist osteoarthrosis and for elbow arthrosis and osteophytosis has been reported in workers exposed to shocks and low-frequency vibration of high magnitude from percussive tools. However, there are too few epidemiology data to enable reliable conclusions to be drawn about exposure-response relationships for both sensorineural disturbances and bone and joint disorders caused by hand-transmitted vibration. Cross-sectional and longitudinal epidemiology studies have shown that occupational exposure to hand-transmitted vibration from a great variety of hand-held tools is significantly associated with an increased occurrence of digital vasospastic disorders called vibration-induced white finger (VWF). The proposal of an exposure-response relationship for VWF has been included in an annex to the international standard ISO 5349. The findings of several epidemiology studies have shown a poor agreement between the risk for VWF observed in various occupational groups and that predicted by the ISO 5349 model. Both overestimation and underestimation of the occurrence of VWF have been reported by investigators. It has been argued that the current ISO frequency-weighting curve for hand-transmitted vibration may be inappropriate for the assessment of vibration-induced adverse vascular effects. Alternative exposure-response relationships for VWF have been suggested in recent epidemiology studies. The epidemiology data used to construct current exposure-response relationships for vibration-induced injuries are primarily derived from cross-sectional studies. Future epidemiology research should be based on prospective cohort studies because the design characteristics of such studies permit the study of cause-effect relationships and the formulation of etiologic hypotheses. [ABSTRACT FROM AUTHOR]

On the basis of data presented in our previous reports, the current study was undertaken to estimate frequency-weighted hand-arm vibration exposure limits for various daily exposure times. The procedures for the present study were as follows. (1) The prevalence of vibration-induced white finger (VWF) as well as the vibration exposure were investigated in various groups of workers operating hand-held vibrating tools. The vibration magnitude of various tools was measured and the results were presented as the energy-equivalent frequency-weighted root-mean-square (m/s2 rms) acceleration. There was a statistically significant positive correlation between the prevalence of VWF and the measured vibration magnitude ( R2=0.5, P<0.05). Hence, it was concluded that in decisions concerning quantitative recommendations for vibration exposure, the prevalence of VWF should be considered. (2) By a careful selection of available publications which contain useful information on duration of vibration exposure of ?2 h/day and the occurrence of VWF, a significant correlation between the prevalence of VWF and the vibration magnitude could be observed. The regression equation was estimated as: y=−18.5+4.6 ( x), R2=0.8. On the basis of this equation, it was speculated that the prevalence of VWF in workers using vibrating tools might be restricted to the prevalence of Raynaud’s phenomenon in the Japanese general population if the 2-h daily vibration exposure is about 4.5 m/s2 rms. (3) Regarding this speculation, the equation provided in the documentation of ISO 5349 was used and modified as: [( ah,w) eq,t=( ah,w)eq,2⋅ (2/ t)1/2 (m/s2 rms)] and then the vibration limit values for daily exposure of 1 min to 8 h were calculated. (4) In order to achieve compatibility with standards of other countries, and to formulate an easy method for using the recommended values presented here, the daily exposure time of 8, 4, 2, 1 and 0.5 h were selected. The correspondence vibration magnitudes were in the range 2.2–9.0 m/s2 rms, and the lower limit (2.2 m/s2 rms) was assumed as the permissible vibration exposure limit for an 8-h working period. The proposed daily vibration limits were then compared with those recommended by other institutions. [ABSTRACT FROM AUTHOR]

In conclusion, it must be stressed that scientific studies need to be undertaken in the near future to solve the various problems mentioned above. These studies should also take account of all the non-occupational factors that, may alter the toxicokinetics and the toxicodynamics of solvents. At present, however, existing data obtained both from experimental research in animals and in volunteers and from studies carried out in workers liable to occupational exposure can be used in preparing lists similar to those we have proposed in Table 1, in which metabolic interferences are reported for the various substances. Although incomplete and only indicative, these lists may be a useful guide to the correct preventive measures to be implemented in various workplace situations. They should, at the very least, stimulate readers to extend their knowledge of the toxicology of combined exposure to solvents. [ABSTRACT FROM AUTHOR]