Effects of single pesticides and binary pesticide mixtures on estrone production in H295R cells.

The aim of the present study was to determine whether the human adrenocortical carcinoma cell line H295R can be used as an in vitro test system to investigate the effects of binary pesticide combinations on estrone production as biological endpoint. In the first step ten pesticides selected according to a tiered approach were tested individually. The anilinopyrimidines cyprodinil and pyrimethanil as well as the dicarboximides iprodione and procymidone increased estrone concentration, while the triazoles myclobutanil and tebuconazole as well as the strobilurins azoxystrobin and kresoxim-methyl decreased estrone concentration in the supernatant of H295R cells. The N-methylcarbamate methomyl did not show any effects, and the phthalimide captan reduced estrone concentration unspecifically due to its detrimental impact on cellular viability. When cyprodinil and pyrimethanil, which belong to the same chemical group and increase estrone production, were combined, in most of the cases the overall effect was solely determined by the most potent compound in the mixture (i.e., cyprodinil). When cyprodinil and procymidone, which belong to different chemical groups but increase estrone production, were combined, in most cases an additive effect was observed. When cyprodinil, which increased estrone production, was combined with either myclobutanil or azoxystrobin, which decreased estrone production, the overall effect of the mixture was in most cases either entirely determined by myclobutanil or at least partially modulated by azoxystrobin. In conclusion, H295R cells appear to be an adequate in vitro test system to study the effect of combining two pesticides affecting estrone production.

Hazard and risk assessment of teratogenic chemicals under REACH.

In 2007, a new European chemicals legislation was implemented: Regulation (EC) No. 1907/2006, also known as "REACH." It obliges companies to take the main responsibility for the valid information on the safe use of the chemicals they manufacture and/or place on the European market. So they must, for example, register their chemicals at the European Chemicals Agency (ECHA) and submit extensive substance-related registration dossiers containing information on the substances' intrinsic hazardous properties and documentation of their risk assessment. REACH regulates the registration and evaluation process as well as the authorization and restriction procedure. In addition, classification, labeling, and packaging of chemicals apply in accordance with Regulation (EC) No. 1272/2008 ("CLP Regulation"). It implements almost completely the provisions of the United Nations Globally Harmonised System of Classification and Labelling of Chemicals (UN GHS) into European legislation and will fully replace the Dangerous Substances Directive (67/548/EEC) and the Dangerous Preparations Directive (1999/45/EC) by 2015. According to both the old and the new classification system, teratogenic chemicals are classified as developmental toxicants, with developmental toxicity falling within the hazard class of reproductive toxicity. REACH as well as the CLP Regulation provide several procedures in which reproductive toxicants take a special position because their harmful effects are considered particularly serious. Teratogenic substances are not explicitly named by these legal texts but, as they constitute as developmental toxicants a hazard differentiation of reproductive toxicity, they are implicitly always included by the provisions.