Exposure minimization

A Guidance Document on Acute Inhalation Toxicity Testing is being developed and presently exists as a draft (OECD 2004b). The document recommends the Acute Toxic Class (ATC) Method with a group size of three animals per sex, if the objective of the test is solely related to hazard classification. Limits for particle-size distribution of aerosolized test substances are suggested. The preferred mode of exposure is the nose-only, head-only, or head/nose-only exposure technique, because this mode of exposure minimizes exposure or uptake by noninhalation routes. 

Total or partial whole-body exposure, minimal or delayed clinical signs. No clinical signs in 3 plus hours after exposure, not life-threatening. Minor blood changes. Clinical observation and treatment of symptoms. Sequential blood samples. 

Clean surface covers have been used extensively at Port Pirie in South Australia to reduce exposure to soils contaminated with Pb as a result of the operation of a smelter on the outskirts of the town (Body et al., 1988). Soils in private gardens with greater than 2 500 mg Pb kg soil were subject to exposure minimization, either by the installation of clean surface cover or by the removal of contaminated material for disposal. 

In December 1980, OSHA and NIOSH jointly published the Health Hazard Alert Benzidine-, o-Tolidme-, and o-Dianisidine-based Dyes [DHHS (NIOSH) Publication No. 81-106] (http //www.cdc.gov/niosh/81-106.html). In this Alert, OSHA and NIOSH concluded that benzidine and benzidine-based dyes were potential occupational carcinogens and recommended that worker exposure be reduced to the lowest feasible level. OSHA and NIOSH further concluded that o-tolidine and o-dianisidine (and dyes based on them) may present a cancer risk to workers and should be handled with caution and exposure minimized. 

SPECIFIC TREATMENT BY EXPOSURE CATEGORY Suspected Exposure Minimal Exposure Mild Exposure Moderate Exposure Moderately Severe Exposure Severe Exposure... 

There are a number of known carcinogenic materials, and the list is growing as the necessary studies of suspected carcinogens are completed. It is recommended that purchases of these be limited and exposures minimized as much as possible to promote the safety of everyone exposed to the materials and in consideration of potential future regulatory restrictions. As discussed in Section 4.III.C, for the purpose of the MSDSs, a listing as a carcinogen by either the NTP, or the lARC is sufficient to be considered as one for the... 

The International Program for Chemical Safety (IPCS) of the World Health Organization has made several recormnendations. Polybrominated diphenyls production (France) and use should be limited because of the concern over high persistency, bioaccumulation and potential adverse effects at low levels. There is limited toxicity data on deca- and octabromodiphenyls. Commercial use should cease unless safety is demonstrated. For the polybrominated diphenyl oxides, a Task Group felt that polybrominated dibenzofurans, and to a lesser extent the dioxins, may be formed. For decabromodiphenyl oxide, appropriate industrial hygiene measures need to be taken and environmental exposure minimized by emission control. Controlled incineration procedures should be instituted. For octabromodiphenyl oxide, the hexa- and lower isomers should be minimized. There is considerable concern over persistence in the environment and the accumulation in organisms, especially, for pentabromodiphenyl oxide. 

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