The term 'mothproofing' describes the treatment of wool or wool-based fabrics to prevent damage by the larvae of a number of insect pests from the order of Coleptera (beetles) and Lepidoptera (butterflies and moths) capable of digesting keratin.

At the end of the 1970s, the pattern of mothproofing agent use altered considerably. The discovery that dieldrin was highly toxic to mammals and aquatic life and also persistent led to a decline in its use and replacement by formulations based on PCSDs (polychloro chloromethyl sulphonamido diphenyl ether); flucofuron and sulcofuron. However, with the advent of formulations based on synthetic pyrethroids, the use of these products has also declined.

Environmental Quality Standards (EQSs) for the protection of saltwater life have been proposed (and were put into legislation in 1989) for the following chemicals used as mothproofing agents;

PCSDs; cyfluthrin; sulcofuron; flucofuron and permethrin.

Sources of mothproofing chemicals include both production and formulation plants and factories where they are used in the treatment of textiles and carpets. Hence, they may enter the aquatic environment, either in direct discharges or in sewage effluents. Since the pyrethroids may have a number of other applications, they may enter the aquatic environment from a number of other sources.

PCSDs , flucofuron and sulcofuron exert their toxic effect on the target organism by inhibiting the synthesis of the enzyme required to break down keratin. Pyrethroids, such as cyfluthrin and permethrin, are neurotoxins (the reader is referred elsewhere on synthetic pyrethroids for an outline of the effects of these chemicals). The summary presented here is therefore mainly limited to information on the remaining three chemicals.

Zabel et al (1988) reviewed the aquatic toxicity and bioaccumulation of these chemicals which is summarised below.

Monitoring data from the National Rivers Authority and the National Monitoring Programme Survey of the Quality of UK Coastal Waters are presented in Appendix D. The information presented suggests that in 1994 some samples of PCSDs in excess of 0.1 mg l^-1 were reported (which would exceed the EQS of 0.05 mg l^-1). However, the data are not highlighted as an exceedence, and since no further information is available, it is not possible to make a further assessment of the data.

Monitoring data were not available for sediments or biota.

Based on available data, it is not possible to assess whether concentrations of mothproofing agents in UK coastal and estuarine waters are likely to exceed relevant quality standards derived for the protection of saltwater life.

From the data available at the time, Zabel et al (1988) were unable to assess the likely fate and behaviour of these chemicals in the aquatic environment.

An exhaustive literature review on the toxicity of mothproofing chemicals to marine organisms has not been carried out for the purposes of this profile. The information provided in this section is taken from existing review documents (Zabel 1988). The most sensitive groups of organisms have been identified.

Environmental data for PCSDs were limited and Zabel et al (1988) stated that further work was necessary to understand their partitioning in the environment. However, the authors concluded that PCSDs readily accumulate in the tissues of fish and were lethal at low concentrations to fish and invertebrates (acute toxic effect were reported at concentrations as low as 1mg l^-1).

Data were also scarce for flucofuron and sulcofuron. However, Zabel et al (1988) concluded that they were less toxic and less likely to accumulate than PCSDs, although, based on the available data they can still be considered to be highly toxic to fish and invertebrates.

PCSDs readily accumulate in the tissues of fish. Flucofuron and sulcofuron are less likely to bioaccumulate than PCSDs.

Potential effects include:

• toxicity of PCSDs to invertebrates and fish at concentrations above the EQS of 0.05 mg l^-1 in the water column;
• toxicity of flucofuron to invertebrates and fish at concentrations above the EQS of 1 mg l^-1 in the water column;
• toxicity of sulcofuron to invertebrates and fish at concentrations above the EQS of 25 mg l^-1 in the water column;
• toxicity of cyfluthrin to saltwater life at concentrations above the EQS of 0.001 mg l^-1 in the water column;
• toxicity of permethrin to saltwater life at concentrations above the EQS of 0.01mg l^-1 in the water column;
• potential for accumulation in sediments, although little is known of the fate and behaviour of these chemicals is known;
• potential for bioaccumulation of PCSDs in fish, birds and Annex II sea mammals.

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