They are identified on global chemical inventories with unique Chemical Abstract Services (CAS) numbers and names. The chemical complexity
of most petroleum substances presents challenges when evaluating their hazards and can result in differing evaluations due to the varying level of hazardous constituents and differences in national chemical control regulations. Global efforts to harmonize the identification of chemical hazards are aimed at promoting the use of consistent hazard evaluation criteria. This paper discusses a systematic approach for the health hazard selleck evaluation of petroleum substances using chemical categories and the United Nations (UN) Globally Harmonized System (GHS) of classification and labeling. Also described are historical efforts to characterize the hazard of these substances and how they led to the development of categories, the identification of potentially hazardous constituents which should be considered, and a summary of the toxicology of the major petroleum
product groups. The use of these categories can increase the utility of existing data, provide better informed hazard evaluations, and reduce the amount of animal testing required. (C) 2013 The Authors. Published by Elsevier Inc. All rights reserved.”
“The biological basis for investigating dichlorodiphenyltrichloroethane (DDT) exposure and breast cancer risk stems from in vitro and animal studies indicating selleck chemicals llc that DDT has estrogenic properties. The objective of this study was to update a meta-analysis from 2004 which found no association between dichlorodiphenyldichloroethylene
(DDE) and breast cancer. We searched PubMed and Web of Science for studies published through June 2012 assessing DDT/DDE exposure and breast cancer. Summary Odds Ratios (ORs) with 95% confidence intervals (CIs) were calculated for the prevalence of breast cancer in the highest versus the lowest exposed groups for DDT and DDE. Difference SDHB of means of exposure for cases versus controls was analyzed for DDT and DDE. From the 500 studies screened, 46 were included in the meta-analysis. Slightly elevated, but not statistically significant summary ORs were found for DDE (1.05; 95% CI: 0.93-1.18) and DDT (1.02; 95% CI: 0.92-1.13). Lipid adjusted difference of means analysis found a significantly higher DDE concentration in cases versus controls (11.30 ng/g lipid; p = 0.01). No other difference of means analysis found significant relationships. The existing information does not support the hypothesis that exposure to DDT/DDE increases the risk of breast cancer in humans. Published by Elsevier Inc.”
“Cardiovascular disease may be induced or worsened by mitochondrion-toxic agents.