Pesticide residues in food shows need for organics
Pesticide residues in the New Zealand diet are being downplayed by the New Zealand Food Safety Authority (NZFSA), according to two advocacy groups. The comments of the Soil & Health Association of NZ and of Pesticide Action Network Aotearoa New Zealand (PAN) follow analysis of two food study results released by the NZFSA.
“The method of reporting of pesticide residues detected in the Total Diet Study (TDS) (1) hides the fact that most composite regional food samples contained pesticide residues, with several having significant multiple residues. It is time for food without pesticide residues – this means organics,” said Soil & Health spokesperson Steffan Browning.
“Analysis of the Food Residue Surveillance Programme (2) results for celery and spinach, showed 100% of the celery samples, and 75% of the spinach samples contained pesticide residues, with many samples containing multiple residues.”
“The celery and spinach were mostly contaminated with chlorothalinol (Bravo) or dithiocarbomates respectively, and sometimes with both. Other toxic pesticides were also found, this showing the need for to boost organic agriculture.”
“Of the celery samples, one had 6 different pesticide residues, one had 3 and three had 2. Fourteen spinach samples had at least 2 pesticide residues. These chemical cocktails are increasingly being shown to be dangerous.”
“The Total Diet Survey, far from giving our produce a clean bill of health has highlighted two persistent problems” said Dr Meriel Watts of Pesticide Action Network Aotearoa New Zealand.
“Tucked away at the back of the document are tables showing that almost all products made with grains such as wheat contains residues of the neurotoxic organophosphate insecticide pirimphos-methyl; and the majority of fruit and vegetables contain dithiocarbmate insecticides.”
“Pirimphos-methyl is used to fumigate grain silos, and there is no chance of removing it from the grain. Organic grain is not treated with this chemical”
“The dithiocarbamate insecticides which turned up in 16 out of 26 of the fruit and vegetables tested, is a perennial problem.”
“It has become very clear that New Zealand simply has to stop using these particular pesticides if we are very going to stop the residue problem,” said Dr Watts.
Dithiocarbamate fungicides and chlorothalonil are on the Pesticide Action Network International list of Highly Hazardous Pesticides for global phase out.
Dithiocarbomate fungicides (eg mancozeb, maneb, thiram) are severe central nervous system toxicant, carcinogen, and endocrine disruptors; they also cause sterility and birth defects, also affecting liver, kidney and respiratory and cardiac, systems. Chlorothalonil is carcinogenic, mutagenic and an environmental toxin and it is thought responsible for aggravating the health effects of other pesticides (3).
A study of cancer patients by Massey University’s Centre for Public Health Research (4) found an elevated leukaemia risk among horticulture workers, with risks to market gardeners and nursery growers, especially women, being higher than those to the general public.
In a separate study released by US government health staff in a recent issue of the American Society of Hematology journal, Blood, (5,6) it was found that exposure to certain pesticides, including dieldrin and chlorothalonil (Bravo) increased the risks 5.6 fold and 2.4 fold respectively, of a blood disorder that can lead to multiple myeloma.
“Considering that dieldrin was banned in agriculture in New Zealand in 1968, and from other uses in 1989, the commonly used fungicide Bravo (chlorothalonil) as found in most non-organic celery, may be a significant culprit in New Zealand cancers. Soil & Health urgently wants studies to focus on Bravo,” said Mr Browning.
Soil & Health has a vision of an Organic 2020.
(3) Lodovici, M. et al. 1994. Effect of a mixture of 15 commonly used pesticides on DNA levels of 8-hydroxy-2-deoxyguanosine and xenobiotic metabolizing enzymes in rat liver. /J. Environ. Pathol. Toxicol. Oncol./13(3):163-168. http://cat.inist.fr/?aModele=afficheN&cpsidt=3483984 Lodovici, M. et al, 1997, Oxidative liver DNA damage in rats treated with pesticide mixtures, /Toxicology/, Volume 117, Issue 1, 14 February 1997, Pages 55-60 http://www.ncbi.nlm.nih.gov/pubmed/9020199. These results indicate that the toxicity of low doses of pesticide mixtures present in food might be further reduced by eliminating diphenylamine and chlorothalonil.