Lowest adverse effects concentrations (LOAECs) for formaldehyde exposure

In 2012 the Committee for Risk Assessment (RAC) of the European Chemicals Agency concluded that 2 ppm formaldehyde represent a Lowest Observed Adverse Effect Concentration (LOAEC) for polypoid adenomas, histopathological lesions and cell proliferation. An analysis of all data shows that a LOAEC of 2 ppm it is not justified for cell proliferation and polypoid adenomas. Higher values are also supported by a new statistical analysis. For histopathological lesions a NOAEC of 1 ppm may be defined but the lesions at 2 ppm cannot be regarded as pre-stages for tumour development. One major uncertainty exists: the description of polypoid adenomas and the lesions at 2 ppm often is insufficient and diagnostic uncertainties can only be resolved by a re-evaluation according to modern histomorphological standards. Although the discrepancy between our assessment and that of RAC may seem rather small we feel the LOAECs proposed by RAC must be challenged taking into consideration the broad data base for formaldehyde and the potential impact of any published RAC opinion on the present discussions about appropriate occupational and indoor exposure limits. (C) 2014 The Authors. Published by Elsevier Inc

The influence of airborne N,N-dimethylformamide on liver toxicity measured in industry workers:A systematic review and meta-analysis

Modern industry is developing and so is the consumption of N,N-dimethylformamide (DMF) and the occupational population exposed to DMF. However, chronic occupational and experimental exposure to DMF has been especially linked to liver and gastrointestinal disturbances

A critical review finds styrene lacks direct endocrine disruptor activity

<div><p>The European Commission lists styrene (S) as an endocrine disruptor based primarily on reports of increased prolactin (PRL) levels in S-exposed workers. The US Environmental Protection Agency included S in its list of chemicals to be tested for endocrine activity. Therefore, the database of S for potential endocrine activity is assessed. In vitro and in vivo screening studies, as well as non-guideline and guideline investigations in experimental animals indicate that S is not associated with (anti)estrogenic, (anti)androgenic, or thyroid-modulating activity or with an endocrine activity that may be relevant for the environment. Studies in exposed workers have suggested elevated PRL levels that have been further examined in a series of human and animal investigations. While there is only one definitively known physiological function of PRL, namely stimulation of milk production, many normal stress situations may lead to elevations without any chemical exposure. Animal studies on various aspects of dopamine (DA), the PRL-regulating neurotransmitter, in the central nervous system did not give mechanistic explanations on how S may affect PRL levels. Overall, a neuroendocrine disruption of PRL regulation cannot be deduced from a large experimental database. The effects in workers could not consistently be reproduced in experimental animals and the findings in humans represented acute reversible effects clearly below clinical and pathological levels. Therefore, unspecific acute workplace-related stress is proposed as an alternative mode of action for elevated PRL levels in workers.</p></div

Oligomers of styrene are not endocrine disruptors

<p>Oligomers of styrene have been identified in polystyrene (PS) polymer samples intended for food packaging. Such oligomers contribute to nonintentionally added substances (NIAS) that may migrate into food or food simulants and therefore have to be assessed for the potential risk to health. No oligomers larger than dimers and trimers of styrene have been found to be present in PS. Some <i>in vivo</i> and <i>in vitro</i> information indicative of an endocrine activity for some specific oligomers suggest concerns for their potential for endocrine disruption in humans. Data on endocrine activity available from <i>in vitro</i> and <i>in vivo</i> screening approaches and from non-guideline studies in experimental animals were evaluated. The different test methods were classified according to the OECD Conceptual Framework for Testing and Assessment of Endocrine Disruptors (OECD) and the ranking system of Borgert et al. proposed in 2014. The quality and reliability of each study is further assessed by professional judgment. The integration of the total information supports the conclusion that neither specific oligomers, nor their mixtures, potentially migrating into food are endocrine disruptors according to the definition of EFSA and WHO/IPCS.</p

A Review of the Implementation of the Embryonic Stem Cell Test (EST)

The EST has been developed as an in vitro screening test for evaluating the potential embryotoxic effects of substances, to allow their classification into three major classes: non-embryotoxic; weakly embryotoxic; and strongly embryotoxic). It is biologically based on the assumption that chemicals with an embryotoxic potential will block the spontaneous development of embryonic stem cells into beating cardiac muscle cells within the first 10 days of embryonic development . In 2002, the assay was endorsed by the ECVAM Scientific Advisory Committee (ESAC) as scientifically validated and ready to be considered for regulatory acceptance and application. the workshop has reviewed the post validated status of the EST so far.JRC.DDG.I.3-In-vitro method