Pesticides may cause NHL, other cancers

Diazinon has been used to control insects in agricultural and residential areas. The IARC said production volumes have been relatively low and decreased further after 2006 due to restrictions in the US and the European Union (EU). There was limited information on the use of this pesticide in other countries.

Tetrachlorvinphos

The insecticide tetrachlorvinphos was classified as “possibly carcinogenic” to humans based on convincing evidence that the agent causes cancer in lab animals. The IARC said the evidence in humans was inadequate.

However, tetrachlorvinphos was shown to induce hepatocellular tumors (benign or malignant) in mice, renal tubule tumors (benign or malignant) in male mice, and spleen hemangioma in male rats.

Tetrachlorvinphos is banned in the EU. In the US, the insecticide is still used on livestock and pets (in flea collars). The IARC said there was no information available on tetrachlorvinphos use in other countries.

Parathion

The insecticide parathion was classified as “possibly carcinogenic” to humans based on convincing evidence that the agent causes cancer in lab animals.

Researchers have observed associations between the insecticide and cancers in several tissues in occupational studies. But the IARC said the evidence that parathion is carcinogenic in humans remains sparse.

Experiments in mice showed that parathion increased the incidence of bronchioloalveolar adenoma and/or carcinoma in males and lymphoma in females. In rats, parathion induced adrenal cortical adenoma or carcinoma (combined), malignant pancreatic tumors, and thyroid follicular cell adenoma in males, and mammary gland adenocarcinoma (after subcutaneous injection in females).

Parathion use has been severely restricted since the 1980s, and all authorized uses of this chemical were cancelled in the EU and the US by 2003.