Chlorine risk assessment

These ongoing risks and consequences associated with these materials depend on the availability of precise knowledge and the formulation of instructions for their correct and responsible use. In particular, those chlorine-based substances which are summarized as biocides, are included in the EC directive 98/8, and regulatory as well as a chlorine risk assessment programs are preceded voluntarily by the industry. 

Hendershot, D. C. (1991b). The Use of Ouantitative Risk Assessment in the Continuing Risk Management of a Chlorine Handling Facility. The Analysis, Communication, and Perception of Risk, ed. B. J. Garrick, and W. C. Gekler, 555-65. New York Plenum Press. 

The Rijnmond area is that part of the Rhine delta between Rotterdam and the North Sea. The Commission for the Safety of the Population at large (COVO) commissioned the study for six chemicals and the operations associated with them acrylonitrile, liquid ammonia, liquid chlorine, LNG, propylene, and part of a separation process (diethanolamine stripper of a hydrodesulfurizer). The study objectives were to evaluate methods of risk assessment and obtain experience with practical applications of these methods. The results were to be used to decide to what extent such methods can be used in formulating safety policy. The study was not concerned with the acceptability of risk or the acceptability of risk reducing measures. 

U.S. Environmental Protection Agency (USEPA). 1990. Risk Assessment for 2378-TCDD and 2378 TCDF Contaminated Receiving Waters from U.S. Chlorine-Bleaching Pulp and Paper Mills. EPA Off. Water Regulations and Standards, Washington, D.C. 154 pp. 

The current situation with regard to risk assessment in the use of several different types of flame retardant is reviewed with respect to EEC council regulation No.793/93. Included in the review are chlorinated, brominated phosphorous and antimony trioxide types of retardant. 0 refs. 

An overview is provided of ongoing risk assessments on halogenated phosphate ester flame retardants in Europe. On the basis of the so-called second and fourth Priority lists on Existing Chemicals (Council Regulation No793/93) three chlorinated phosphate ester flame retardants are selected. The selection is based on their hazard profile, volume and use pattern. The three substances involved are TCPP, TDCP and TCEP (Antiblaze V6 from Albemarle is also involved but, due to confidentiality, is not discussed. An outline is provided from a European point of view on topics such as methodology of risk analyses, data-gaps and worst case approach, industry involvement, downstream participation and possible impact of final report on industry. 2 refs. 

The issues of mercury cell phase out and risk assessment of chlorine compounds. 

While participating in the European Union programme on risk assessment of existing chemicals, Euro Chlor (representing all major European chlorine producers), recognised the need to carry out a detailed risk evaluation on chemicals linked to the production of chlorine. In view of concerns about specific risks of organohalogen compounds to the marine environment as a sink for all watercourses, Euro Chlor focused on this environmental compartment, with emphasis on the North Sea. This sea area has been extensively studied and is controlled by the Oslo and Paris Convention for the Prevention of Marine Pollution (OSPARCOM). For a series of chemicals on lists of concern adopted by the North Sea Conference (1990), risk assessments are being carried out to demonstrate their variable environmental profiles. 

The chlorinated chemicals assessed do not have the same risk profile. For the more volatile chemicals the safety margins between the actual exposure and the level at which no effect on the environment would be expected is quite high. For more persistent chemicals there is a need to look to the environmental compartment where they can be accumulated (mainly in sediments and biota). For some of these chemicals the safety margin is quite low and in worst-case situations serious effects may occur. For the very persistent, bioaccumulative and toxic chemicals (like dioxins, PCBs and DDT), acceptable environmental concentrations are so low and difficult to control that the industry is committed to reducing as far as possible releases to the environment through application of Best Available Techniques (BAT), mainly with respect to dioxins. For other chemicals (PCBs, DDT), production has already been halted for some years. 

Note that some of the risk information is actuarial (based on statistical data, typically collected and organized by insurance companies), and some of it has been derived from the type of risk assessment discussed in this book (chloroform in chlorinated drinking water, afla-toxin in peanut products). While the uncertainties associated with the figures in Table 11.2 are much greater for some risks than for others (not a trivial problem in presentation of risk data), such a presentation, it would seem, is helpful to people who are trying to acquire some understanding of extremely low probability events, of the order of one-in-one million. 

Ecotoxicological Risk Assessment for Chlorinated Organic Chemicals. Alliston, Ontario, Canada, 25 to 29 Jul 1994. Published by SETAC, 1998. Application of Life-Cycle Assessment to Public Policy. Wintergreen, Virginia, 14 to 19 Aug 1994. Published by SETAC, 1997. 

PCBs (polychlorinated biphenyls) A family of chemicals composed of biphenyl molecules that have been chlorinated to varying degrees, performance assessment A type of risk assessment in which the potential long-term impacts of hazardous waste disposal on human health and the environment are evaluated for the purpose of determining whether disposal of specific wastes at specific sites should be acceptable, persistence The length of time that a contaminant persists in the environment. 

Ebert E, Price P, Keenan R. 1996. Estimating exposures to dioxin-like compounds for subsistence anglers in North American. In Human exposure, human health risk assessment, and organohalogen compounds, 16th Symposium on Chlorinated Dioxins and Related Compounds, Amsterdam Holland, volume 30, 66-69. 

EPA. 1987e. Interim procedures for estimating risks associated with exposure to mixtures of chlorinated dibenzo-p-dioxins and dibenzo furans (CDDs and CDFs). Risk Assessment Forum. Washington, DC U.S. Environmental Protection Agency EPA report no. 625/3-87/012. 

Pohl HR, Hibbs BF. 1996. Breast-feeding exposure of infants to environmental contaminants - a public health risk assessment viewpoint chlorinated dibenzodioxins and chlorinated dibenzofurans. Toxicol Indust Health 12(5) 105-114. 

Rozman K, Roth WL, Greim H, et al. 1993. Relative potency of chlorinated dibenzo-p-dioxins (CDDs) in acute, subchronic and chronic (carcinogenicity) toxicity studies Implications for risk assessment of chemical mixtures. Toxicology 77(l-2) 39-50. 

Quantitative risk assessments have been performed on a variety of flame-retardants used both in upholstered furniture fabric and foam. The National Research Council performed a quantitative risk assessment on 16 chemicals (or chemical classes) identified by the U.S. Consumer Product Safety Commission (CPSC). The results were published in 2000.88 The 16 flame-retardants included in this NRC study were HBCD, deca-BDE, alumina trihydrate, magnesium hydroxide, zinc borate, calcium and zinc molybdates, antimony trioxide, antimony pentoxide and sodium antimonate, ammonium polyphosphates, phosphonic acid, (3- [hydroxymethyl]amino -3-oxopropyl)-dimethylester, organic phosphonates, tris (monochloropropyl) phosphate, tris (l,3-dichloropropyl-2) phosphate, aromatic phosphate plasticisers, tetrakis (hydroxymethyl) hydronium salts, and chlorinated paraffins. The conclusions of the assessment was that the following flame-retardants can be used on residential furniture with minimal risk, even under worst-case assumptions ... 

A. Tukker, Frames in the Toxicity Controversy Risk Assessment and Policy Analysis Related to the Dutch Chlorine Debate and the Swedish PVC Debate, Kluwer Academic Publishers, Dordrecht, The Netherlands, 1999, p.21. 

F.M. Christensen S.I. and Olson, Risk assessment of Short and Medium Chain Chlorinated Paraffin s (SCCP and MCCP), Technical Report, Technical University of Denmark, 2002. 

The database on chlorine is robust. The irritant properties and toxicity of chlorine have been studied with controlled human exposures as well as with multiple species of laboratory animals. Exposure durations range from acute to chronic. Subjects with rhinitis or asthma appear to be more sensitive to the irritant effects of chlorine than healthy individuals. Thus, risk assessment addresses the potential for greater effects in these sensitive populations. 

US EPA (1985) Risk Assessment for chlorinated paraffins Effect on fish and wildlife. Environmental Protection Agency, Health and Environmental Review Division, Toxicology Section, Washington DC, Dec. 18,1985... 

Barnes DG, Kutz FW, and Bottimore DP (1989) Update to the Interim Procedures for Estimating Risks Associated with Exposures to Mixtures of Chlorinated Dibenzo-p-Dioxins and -Dibenzofurans (CDDs and CDEs). Risk Assessment Forum. Washington, DC US EPA. 

Many chemical risks such as those of chloroform in drinking water, are calculated, not measured - that is, they are based not only on scientific data, but also on various sets of assumptions and extrapolation models that, while scientifically plausible (they fall within the bounds of acceptable biological theory), have not been subjected to empirical study and verification. Indeed, the results of most risk assessments - whether expressed as an estimate of extra cancer risk or an ADI - are scientific hypotheses that are not generally testable with any practicable epidemiological method. There is, for example, no practical means to test whether chloroform residues in chlorinated drinking water increase lifetime cancer risk in humans by 8 in 1000000, as hypothesized above. The tools of epidemiology are enormously strained, indeed, when called upon to detect the relatively low risks associated with most environmental chemicals. Without such a test, these risks remain unverified. 

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