Pesticides may cause NHL, other cancers

 

 

Farmer spraying pesticide

Photo by John Messina

 

The International Agency for Research on Cancer (IARC), the specialized cancer agency of the World Health Organization, has found evidence suggesting that 5 organophosphate pesticides may be carcinogenic.

The IARC classified the herbicide glyphosate and the insecticides malathion and diazinon as “probably carcinogenic” to humans and the insecticides tetrachlorvinphos and parathion as “possibly carcinogenic” to humans.

A summary of these findings has been published in The Lancet Oncology.

Glyphosate

For the herbicide glyphosate, the IARC found limited evidence of carcinogenicity in humans. Case-control studies of occupational exposure to glyphosate in the US, Canada, and Sweden showed increased risks for non-Hodgkin lymphoma (NHL).

However, the Agricultural Health Study (AHS) showed no significantly increased risk of NHL in subjects exposed to glyphosate.

A study of community residents showed increases in blood markers of chromosomal damage after glyphosate formulations were sprayed nearby. And glyphosate was shown to cause DNA and chromosomal damage in human cells, although bacterial mutagenesis tests were negative.

In studies of male mice, glyphosate increased the incidence of renal tubule carcinoma and hemangiosarcoma. Glyphosate also increased the incidence of pancreatic islet-cell adenoma in male rats, and a glyphosate formulation promoted skin tumors in mice.

The IARC said glyphosate has the highest global production volume of all herbicides. It is used in agriculture, forestry, urban, and home applications.

Glyphosate has been detected in the air during spraying, in water, and in food. The general population is exposed to the chemical primarily by living near sprayed areas, home use, and diet. But the IARC said the level of exposure observed is generally low.

Malathion

The IARC classified malathion as “probably carcinogenic” for humans based on limited evidence linking the insecticide to NHL and prostate cancer. Occupational use of malathion was associated with an increased risk of prostate cancer in a Canadian case-control study and in the AHS.

Studies of occupational exposures in the US, Canada, and Sweden revealed positive associations between malathion and NHL. However, results of the AHS did not show an association between the insecticide and NHL.

Studies showed that malathion induced DNA and chromosomal damage in humans and animals, although bacterial mutagenesis tests were negative. Results also suggested malathion disrupts hormone pathways.

Experiments in mice showed malathion increased the incidence of hepatocellular adenoma or carcinoma (combined). In rats, the insecticide increased the incidence of thyroid carcinoma in males, hepatocellular adenoma or carcinoma (combined) in females, and mammary gland adenocarcinoma after subcutaneous injection in females.

The IARC said malathion is used in “substantial volumes throughout the world” to control insects in agricultural and residential areas.

Workers may be exposed to malathion during the use and production of the product. The general population may be exposed if they live near sprayed areas, use the product at home, or consume food exposed to the chemical.

Diazinon

The IARC classified diazinon as “probably carcinogenic” for humans based on limited evidence linking the insecticide to NHL, leukemia, and lung cancer.

Two multicenter, case-control studies of agricultural exposures suggested a positive association between diazinon and NHL. The AHS showed positive associations with specific subtypes of NHL but no overall increased risk of NHL. The AHS also suggested an increased risk of leukemia and lung cancer in subjects exposed to diazinon.

Evidence suggested that diazinon induced DNA or chromosomal damage in human and mammalian cells in vitro. In vivo, diazinon increased the incidence of hepatocellular carcinoma in mice and leukemia or lymphoma (combined) in rats, but only in males receiving the low dose in each study.

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.

 

 

Farmer spraying pesticide

Photo by John Messina

 

The International Agency for Research on Cancer (IARC), the specialized cancer agency of the World Health Organization, has found evidence suggesting that 5 organophosphate pesticides may be carcinogenic.

The IARC classified the herbicide glyphosate and the insecticides malathion and diazinon as “probably carcinogenic” to humans and the insecticides tetrachlorvinphos and parathion as “possibly carcinogenic” to humans.

A summary of these findings has been published in The Lancet Oncology.

Glyphosate

For the herbicide glyphosate, the IARC found limited evidence of carcinogenicity in humans. Case-control studies of occupational exposure to glyphosate in the US, Canada, and Sweden showed increased risks for non-Hodgkin lymphoma (NHL).

However, the Agricultural Health Study (AHS) showed no significantly increased risk of NHL in subjects exposed to glyphosate.

A study of community residents showed increases in blood markers of chromosomal damage after glyphosate formulations were sprayed nearby. And glyphosate was shown to cause DNA and chromosomal damage in human cells, although bacterial mutagenesis tests were negative.

In studies of male mice, glyphosate increased the incidence of renal tubule carcinoma and hemangiosarcoma. Glyphosate also increased the incidence of pancreatic islet-cell adenoma in male rats, and a glyphosate formulation promoted skin tumors in mice.

The IARC said glyphosate has the highest global production volume of all herbicides. It is used in agriculture, forestry, urban, and home applications.

Glyphosate has been detected in the air during spraying, in water, and in food. The general population is exposed to the chemical primarily by living near sprayed areas, home use, and diet. But the IARC said the level of exposure observed is generally low.

Malathion

The IARC classified malathion as “probably carcinogenic” for humans based on limited evidence linking the insecticide to NHL and prostate cancer. Occupational use of malathion was associated with an increased risk of prostate cancer in a Canadian case-control study and in the AHS.

Studies of occupational exposures in the US, Canada, and Sweden revealed positive associations between malathion and NHL. However, results of the AHS did not show an association between the insecticide and NHL.

Studies showed that malathion induced DNA and chromosomal damage in humans and animals, although bacterial mutagenesis tests were negative. Results also suggested malathion disrupts hormone pathways.

Experiments in mice showed malathion increased the incidence of hepatocellular adenoma or carcinoma (combined). In rats, the insecticide increased the incidence of thyroid carcinoma in males, hepatocellular adenoma or carcinoma (combined) in females, and mammary gland adenocarcinoma after subcutaneous injection in females.

The IARC said malathion is used in “substantial volumes throughout the world” to control insects in agricultural and residential areas.

Workers may be exposed to malathion during the use and production of the product. The general population may be exposed if they live near sprayed areas, use the product at home, or consume food exposed to the chemical.

Diazinon

The IARC classified diazinon as “probably carcinogenic” for humans based on limited evidence linking the insecticide to NHL, leukemia, and lung cancer.

Two multicenter, case-control studies of agricultural exposures suggested a positive association between diazinon and NHL. The AHS showed positive associations with specific subtypes of NHL but no overall increased risk of NHL. The AHS also suggested an increased risk of leukemia and lung cancer in subjects exposed to diazinon.

Evidence suggested that diazinon induced DNA or chromosomal damage in human and mammalian cells in vitro. In vivo, diazinon increased the incidence of hepatocellular carcinoma in mice and leukemia or lymphoma (combined) in rats, but only in males receiving the low dose in each study.

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.

 

 

Farmer spraying pesticide

Photo by John Messina

 

The International Agency for Research on Cancer (IARC), the specialized cancer agency of the World Health Organization, has found evidence suggesting that 5 organophosphate pesticides may be carcinogenic.

The IARC classified the herbicide glyphosate and the insecticides malathion and diazinon as “probably carcinogenic” to humans and the insecticides tetrachlorvinphos and parathion as “possibly carcinogenic” to humans.

A summary of these findings has been published in The Lancet Oncology.

Glyphosate

For the herbicide glyphosate, the IARC found limited evidence of carcinogenicity in humans. Case-control studies of occupational exposure to glyphosate in the US, Canada, and Sweden showed increased risks for non-Hodgkin lymphoma (NHL).

However, the Agricultural Health Study (AHS) showed no significantly increased risk of NHL in subjects exposed to glyphosate.

A study of community residents showed increases in blood markers of chromosomal damage after glyphosate formulations were sprayed nearby. And glyphosate was shown to cause DNA and chromosomal damage in human cells, although bacterial mutagenesis tests were negative.

In studies of male mice, glyphosate increased the incidence of renal tubule carcinoma and hemangiosarcoma. Glyphosate also increased the incidence of pancreatic islet-cell adenoma in male rats, and a glyphosate formulation promoted skin tumors in mice.

The IARC said glyphosate has the highest global production volume of all herbicides. It is used in agriculture, forestry, urban, and home applications.

Glyphosate has been detected in the air during spraying, in water, and in food. The general population is exposed to the chemical primarily by living near sprayed areas, home use, and diet. But the IARC said the level of exposure observed is generally low.

Malathion

The IARC classified malathion as “probably carcinogenic” for humans based on limited evidence linking the insecticide to NHL and prostate cancer. Occupational use of malathion was associated with an increased risk of prostate cancer in a Canadian case-control study and in the AHS.

Studies of occupational exposures in the US, Canada, and Sweden revealed positive associations between malathion and NHL. However, results of the AHS did not show an association between the insecticide and NHL.

Studies showed that malathion induced DNA and chromosomal damage in humans and animals, although bacterial mutagenesis tests were negative. Results also suggested malathion disrupts hormone pathways.

Experiments in mice showed malathion increased the incidence of hepatocellular adenoma or carcinoma (combined). In rats, the insecticide increased the incidence of thyroid carcinoma in males, hepatocellular adenoma or carcinoma (combined) in females, and mammary gland adenocarcinoma after subcutaneous injection in females.

The IARC said malathion is used in “substantial volumes throughout the world” to control insects in agricultural and residential areas.

Workers may be exposed to malathion during the use and production of the product. The general population may be exposed if they live near sprayed areas, use the product at home, or consume food exposed to the chemical.

Diazinon

The IARC classified diazinon as “probably carcinogenic” for humans based on limited evidence linking the insecticide to NHL, leukemia, and lung cancer.

Two multicenter, case-control studies of agricultural exposures suggested a positive association between diazinon and NHL. The AHS showed positive associations with specific subtypes of NHL but no overall increased risk of NHL. The AHS also suggested an increased risk of leukemia and lung cancer in subjects exposed to diazinon.

Evidence suggested that diazinon induced DNA or chromosomal damage in human and mammalian cells in vitro. In vivo, diazinon increased the incidence of hepatocellular carcinoma in mice and leukemia or lymphoma (combined) in rats, but only in males receiving the low dose in each study.

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.