DAKAR, Senegal (PANA)�Around 30 percent of pesticides marketed in developing countries with an estimated market value of $300 million annually do not meet internationally accepted quality standards, two UN agencies said Feb. 1.

The chemicals are posing a serious threat to human health and the environment, the UN Food and Agriculture Organization (FAO) and the World Health Organization (WHO) warned in a joint press statement.

FAO and WHO said that the problem of poor-quality pesticides is particularly widespread in sub-Saharan Africa, where quality control is generally weak.

"These poor-quality pesticides frequently contain hazardous substances and impurities that have already been banned or severely restricted elsewhere," said Gero Vaagt, of the FAO Pesticide Management Group.

Such pesticides, he added, often contribute to the accumulation of obsolete pesticide stocks in developing countries.

The global market value for pesticides was estimated at $32 billion in 2000, with the share of developing countries around $3 billion.

In developing countries, pesticides are mainly used for agriculture, but also for public health, such as insecticides for controlling insects spreading malaria.

Possible causes of low quality of pesticides can include both poor production and formulation and the inadequate selection of chemicals.

"In many pesticide products, for example, the active ingredient concentrations are outside internationally accepted tolerance limits," said Dr. David Heymann, a WHO official who specializes in communicable diseases.

"In addition, poor-quality pesticides may be contaminated with toxic substances or impurities," he added.

When the quality of labeling and packaging is also taken into account, the proportion of poor-quality pesticide products in developing countries is even higher.

"The labeling often written in improper language fails to provide data on the active ingredient, application, date of manufacture and safe handling of the chemical," the UN agencies said.

For the consumer, the label is often the only source of product information that can guarantee a safe and effective use of the chemical. But falsely declared products continue to find their way to markets for years without quality control, WHO said.

The UN agencies urged governments, international and regional organizations to adopt the worldwide accepted FAO/WHO pesticide specifications to ensure the production and trade of good quality products.

Countries should make these voluntary standards legally binding, they said.

The FAO/WHO standards are especially important for developing countries that lack the infrastructure for proper evaluation of pesticide products.

Pesticide industries, including producers of generic pesticides, should submit their products for quality assessment to FAO/WHO.

In a memorandum of understanding signed between FAO and WHO, the two organizations have agreed to co-operate in a joint program to develop specifications for pesticides.

This unified procedure would enhance the development of high quality standards for pesticides, leading to improved human and environmental safety as well as to more sustainable agriculture production, they said.