Environmental Project, 941 – Substance flow analysis of 4-nitrotoluen

Substance Flow Analysis of 4-nitrotoluene

4 Exposure of humans and the environment

4.1 Consumption as trace element and unintended uses as contaminant

Since there do not seem to exist any significant applications of 4-nitrotoluene in Denmark there will not be any exposure of the environment from manufacturing processes or use of the substance.

4.1 Consumption as trace element and unintended uses as contaminant

Despite that no applications of 4-nitrotoluene seems to take place in Denmark that may still be an exposure of the substance as unintended contaminant.

One analysis for 4-nitrotoluene has been found in the literature. 17 textiles and laundry sewage samples were analyzed for a content of 4-nitrotoluene because it is used in the manufacture of raw material for production of dyestuff. Two textiles and one laundry sewage sample contained 4-nitrotoluene. The amount of 4-nitrotoluene in the textiles corresponded to less than 6 mg/kg textile and the content in the sewage corresponded to 0.016 mg/kg (Larsen et al., 2000).

The content of 4-nitrotoluene may result in dermal exposure. Larsen et al. (2000) makes the following estimate of the potential exposure based on measurements of 4-nitrotoluene in textiles: If 0.5 kilo of clothes contains maximum 3 mg of 4-nitrotoluen and it is assumed that a child of 10 kilo absorbs all the 4-nitrotoluene, the exposure is equivalent to approximately 0.3 mg/kg body weight, i.e. about 6,500 times below the LD₅₀ for rats. The authors states that it is difficult to estimate the exposure concern based on the figures, but it is concluded that acute clinical effects cannot be expected (Larsen et al., 2000).

4-nitrotoluen can also be emitted to air, which may affect human health, if the textile is stored in a small room with poor ventilation. If 20 sheets of 0.5 kilo are stored in a room of 3 x 4 x 2.5 meters and the entire content of 4-nitrotoluene is released to the air, the maximum concentration can reach 2 mg/m³. This is 6 times below the occupational exposure limit, thus the exposure is not considered a significant health concern (Larsen et al., 2000). This is supported by other literature sources. IUCLID also mentions that exposure to the substance in the workplace can occur by inhalation of vapour and absorption through intact skin. Basic atmospheric monitoring indicates that exposure by inhalation is generally well below the occupational exposure standard (UK) (IUCLID, 2000).