Chemical of concern

If the chemicals of concern contain more than eight carbon atoms, then they tend to have a high soil adsorption. 

I Chemicals on ttie original list that do not meet the toxldty criteria but because of their high production volume and recognized toxldty are considered chemicals of concern ( Other chemicals ). 

The list of chemicals with endocrine-disrupting activity has increased considerably with the systematic screening of chemicals employing some of the methods described in the previons section. Here we expand on the list of known EDCs to illustrate the diversity of chemicals of concern, but the list is by no means exhaustive. 

Measurement of exposure can be made by determining levels of toxic chemicals in human serum or tissue if the chemicals of concern persist in tissue or if the exposure is recent. For most situations, neither of these conditions is met. As a result, most assessments of exposure depend primarily on chemical measurements in environmental media coupled with semi-quantitative assessments of environmental pathways. However, when measurements in human tissue are possible, valuable exposure information can be obtained, subject to the same limitations cited above for environmental measurement methodology. Interpretation of tissue concentration data is dependent on knowledge of the absorption, excretion, metabolism, and tissue specificity characteristics for the chemical under study. The toxic hazard posed by a particular chemical will depend critically upon the concentration achieved at particular target organ sites. This, in turn, depends upon rates of absorption, transport, and metabolic alteration. Metabolic alterations can involve either partial inactivation of toxic material or conversion to chemicals with increased or differing toxic properties. 

Many individuals and organizations start down the path to green chemistry by first becoming aware of chemicals of concern in the products that they make or use. This awareness may come via regulations, internal priorities or external pressure from concerned stakeholders. Chemicals of concern satisfy two requirements ... 

In addition to regulated chemicals, examples of hazard categories that may be selected for identifying chemicals of concern include but are not limited to Box 8.1. 

Appendix 1 contains a number of references and links to chemical lists and resources to help identify chemicals of concern. In addition, it maybe useful to review the criteria used to classify substances via EU s Dangerous Substance Directive (67/548/EEC), Environment Canada s Ecological Categorization of Substances on the Domestic Substances List, or Health Canada s Categorization of Substances on the Domestic Substances List when establishing your organization s criteria for selecting chemicals of concern. 

Chemicals of concern can also be defined based on hazard criteria that apply to chemicals regardless of whether or not they are on regulatory or policy hsts. Below we describe several tools that can help businesses to identify chemicals of concern through modehing programs and by tracking regulatory hsts around the world. 

There are a number of commerciahy available database tools that support regulatory comphance and the identification of chemicals of concern based on regulatory or policy lists. 

Whether voluntarily or not, as companies phase out chemicals of concern, they are subsequently faced with the challenging task of finding alternative chemicals or processes to serve the same desired functions. Simply because a chemical is not a known hazard does not make it benign. To avoid going from the frying pan to the fire so to speak, it is necessary to assess and compare alternatives. In this section we describe several tools and approaches for assessing the human and environmental health and safety aspects of chemicals. They include ... 

Ehminating chemicals of concern often starts as a reactive strategy but it is an important first step on the path to implementing greener chemical inventories. In this section, we discuss two initiatives that focus on eliminating chemicals of concern. While we use an example from a very large company, their approach can be applied by small and large businesses ahke. 

Safer Detergent Stewardship Initiative (SDSI). An example of a program that focuses on eliminating chemicals of concern is the US EPA DfE Program s SDSL... 

Eliminating chemicals of concern can lead a company to become more proactive by creating demand for greener alternatives and by positively defining chemicals. While it may appear at first to be restrictive in terms of disallowing chemicals, in practice it tends to drive innovation and lead to the development of new chemicals and products - part of what makes green chemistry so attractive to people of widely divergent views. 

The need to evaluate alternatives often arises once the decision to eliminate chemicals of concern is made. Sometimes a chemical of concern can be eliminated through product design such as through the use of a material that is inherently flame retardant or a fabric barrier without the need for added flame-retardant chemicals. But when the only currently feasible option appears to be a chemical substitution, then the alternatives must be evaluated and assessed to ensure that they are in fact greener than the chemical they are intended to replace. We provide as examples of implementing alternatives assessment, the Green Screen for Safer Chemicals and the DfE Flame Retardants in Printed Circuit Boards Partnership. 

A Resources to identify chemicals of concern B Chemical toxicity C Exposure assessment tools D Hazard and risk assessment tools E Safer chemistry design tools... 

The Danish List of Undesirable Substances is a list of chemicals of concern that the government believes should be avoided to the extent feasible in commerce. Using a systematic analysis, substances are selected automatically if they meet some clear and defined criteria, for example, problematic classifications, because they are imder suspicion for being PBT/vPvB (Persistent, Bioaccumulative, Toxic/very Persistent, very Bio accumulative) or endocrine-disrupting. 

Pesticides used on crops grown on the test site in previous seasons may also have an impact on the outcome of a field residue trial. Carryover of prior pesticide applications could contaminate samples in a new trial, complicate the growth of the crop in a trial, or cause interference with procedures in the analytical laboratory. For this reason, an accurate history of what has transpired at the potential test site must be obtained before the trial is actually installed. The protocol should identify any chemicals of concern. If questions arise when the history is obtained, they should be reviewed with the Study Director prior to proceeding with the test site. In most annual crop trials, this will not be a significant issue owing to crop rotations in the normal production practices, because the use of short residual pesticides and different chemical classes is often required for each respective crop in the rotation. However, in many perennial crops (tree, vines, alfalfa, etc.) and monoculture row crops (cotton, sugarcane, etc.), the crop pesticide history will play a significant role in trial site selection. 

Testing for cardiac sensitization consists of establishing a background (control) response to an injection of epinephrine followed by a second injection during exposure to the chemical of concern (Reinhardt et al. 1971). The dose of epinephrine chosen is the maximum dose that does not cause a serious arrhythmia (NRC 1996). Because a second injection of epinephrine during air exposure often induces a mild cardiac response, Reinhardt et al. (1971) con... 

EPA plans to follow up on selected new chemicals during the commercialization phase. This program will be focused on those chemicals of concern as well as those for which there is uncertainty concerning toxic effects. Unrestricted commercialization could lead to substantial increases in exposure so that it may be necessary to reassess the risk through additional testing. TSCA grants EPA the authority to do so under Sections 5(a)(2) and 8(a) but voluntary action will be sought where appropriate. 

Bioaccumulative chemicals of concern (BCCs) Endrin aldehyde ... 

The assessment of whether a substance presents a risk to the receiving environmental compartment is based on a comparison of the measured or predicted environmental concentration (PEC) of the chemical of concern with the predicted no effect concentration (PNEC) to organisms in the ecosystem. This is briefly discussed in Chapter 7.4. Studies carried out so far, e.g. by Vandepitte and Feijtel [91], show that the risk of anionic surfactants such as LAS, AE and AES for the aquatic environment is low, since the PECs are always lower than the maximum permissible concentrations. 

The relative ratio of volatilization to bioremediation depends on Henry s law constant, solubility, and biodegradability of the chemicals of concern. Many hydro-... 

Although the goals or endpoints of SPMD studies vary widely, a number of questions should at least be considered prior to initiation of exposures. These questions include the following 1) are there threshold limit values (air) or water quality criteria for chemicals of concern, and if so, has the lowest environmental concentration of concern (Cc) been established for target compounds 2) will study... 

As a basis for protection of human health and the environment from chemicals of concern, the Substitution Principle has several advantages ... 

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