Environmental risks associated with chemicals

QRA can be used to investigate many types of risks associated with chemical process facilities, such as the risk of economic losses or the risk of environmental impact. But, in health and safety applications, the use of QRA can be classified into two categories ... 

Green chemistry seeks to reduce or eliminate the risk associated with chemical activity by reducing or eliminating the hazard side of the risk equation, thereby obviating the need for exposure controls and, more importantly, preventing environmental... 

Companies are beginning to evaluate and account for nature and the true environmental costs and risks associated with chemical refining and manufacturing, the impact to natural capitalism. Natural capital refers to all of the resources used... 

Growth of the chemical industry has been more moderate since 1970. But during this third period, a combination of factors has Increased almost exponentially the focus on risks associated with chemicals, health and the environment. These factors Include advances in health and environmental technology, an increasing corporate responsibility toward health and environmental concerns, media spotlighting of new information cmd incidents, and increasing government and public Involvement in risk decisions. 

The United States government produces many publications which will assist those assessing risks associated with chemical substances. The most important way in which details of publications are made known is through the US National Technical Information Service (NTIS) which produces Government Reports Announcements and Index, a fortnightly listing of abstracts of reports [2]. NTIS also publishes a series of weekly Abstract Newsletters on topics such as chemistry, and environmental polluticm and control. 

Under the Toxic Substances Control Act (TSCA), numerous nomenclature issues have arisen over the years, some of which have been discussed in this book. There will undoubtedly be new nomenclature issues to be resolved, nanoparticles being a current case in point. Issues of the past have often arisen out of administrative and sometimes arbitrary naming conventions, but risks associated with chemical substances do not depend on how they are named. Nanoparticles present different issues in the sense that the Environmental Protection Agency (EPA) stated that the TSCA regulates chemical substances of a particular molecular identity, without regard to physical properties such as size and shape. Potential for significant risk due to nanoparticles clearly exists exactly due to those physical properties. Regulators and interpreters of the TSCA must address potential risks such substances may pose even if their non-nano counterparts do not, and even if their newness does not meet the current definition of substances with different molecular identities. 

The determination of the potential risk associated with chemical use and dermal exposure to environmental contaminants is often based on an evaluation of in vivo and in vitro dermal absorption in the rat together with in vitro evaluation using... 

Such qualified specialists could be persons (1) who, because of education, training, or experience, or a combination of these factors, is capable of understanding the health and environmental risks associated with the chemical substance which is handled under his or her supervision, (2) who is responsible for enforcing appropriate methods of handling, treating and disposing of chemicals to minimize risks, and (3) who is responsible for the safety assessments and clearances related to the procurement, storage, use, and disposal of the chemical substance as may be appropriate or required. 

The regulatory requirements for the R D exemption fall into three categories. First, the chemical substance must be made only in small quantities solely for research and development. Second, the manufacturer or importer must evaluate the known health and environmental risks associated with the substance and notify anyone who handles the chemical about those health risks. Third and finally, the R D chemical must only be used by a technically quahfied individual or under that individual s direct supervision. ... 

The TSCA inventory (a list of 70,000 toxic chemicals) was established to record all products manufactured, imported, sold, processed, or used for commercial purposes. Exemptions include R D chemicals and by-products without commercial purpose. The TSCA also controls premanufacture review of new chemical substances, risk assessment by testing and information gathering, recordkeeping and reporting on health and environmental effects associated with chemical substances, and restrictions on known hazardous chemicals. 

Most hydraulic fluid preparations start as chemical mixtures. For instance, there is a considerable area of overlap in the specific petroleum hydrocarbon chemicals contained in the mineral oil and polyalphaolefin hydraulic fluids. For all classes of hydraulic fluids, there may be similarities with other original products intended for use as lubricants. The complications involved in documenting the environmental fate of mixtures increase under conditions encountered at many NPL sites, where it may be hard to determine the precise original product associated with chemicals identified at an area in need of remediation. In most instances, available peer-reviewed literature, supplemented with data obtained from manufacturers of particular formulations and information in trade magazines, can supply information about the original hydraulic fluid preparations. At NPL sites, site-specific evaluations of specific chemicals may be the only feasible way to address concerns over environmental fate and potential exposure risks. 

Furthermore, and this is linked to the complete preferences, the hypothetical market environmental goods and services is not a market under perfect competition. The existence of externalities is one reason for this, which is why environmental economists try to value externalities. But the condition of perfect knowledge isn t there either. The reason is simple we still don t have all the information about environmental degradation and risks associated with the use of, for example, chemicals. 

Several studies have suggested that some critical adverse effects like peroxisome proliferation, hepatotoxicity, immunotoxicity, and developmental toxicity may be associated with chemical exposure to PFCs, particularly to PFOS (perfluorooctane sulfonate) and PFOA (perfluorooctanoic acid), two ubiquitous persistent organic pollutants with possible environmental and human health risks. 

EPA. 1991a. Alpha2 1-globulin association with chemically induced renal toxicity and neoplasia in the male rat. Washington, DC U.S. Environmental Protection Agency, Risk Assessment Forum. EPA/625/3-91/019F. 

To aid in assessing the risks associated with large numbers of environmental contaminants, quantitative-structure-activity relationships (QSARs) have been developed covering nearly all biological effects or other endpoints in both aquatic and terrestrial species (Connell, 1990). QSARs relate chemical structural... 

Given the potential environmental consequences of chemical exposure by the disposal of dredged material worldwide, it is vital that we improve our understanding of its impact on the environment. Through an improved understanding we can minimize the risks associated with the disposed dredged materials. 

Tolbert, P.E., Eisen, E.A., Pothier, L.J., Monson, R.R., Hallock, M.F. Smith, T.J. (1992) Mortality studies of machining fluid exposure in the automobile industry. II. Risks associated with specific fluid types. Scand. J. Work Environ. Health, 18, 351-360 Verschueren, K. (1996) Handbook of Environmental Data on Organic Chemicals, 3rd Ed., New York, Van Nostrand Reinhold, pp. 753-756 Waechter, J.M., Bormett, G.A. Stewart, H.S. (1995) Diethanolamine Pharmacokinetics in Sprague-Dawley Rats Following Dermal or Intravenous Administration, Midland, MI, Dow Chemical Company... 

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