You’ve heard of a tempest in a teapot. This is a hurricane in a thimble. I’m talking about a study carried out by Canada’s Food Inspection Agency that found pesticide residues in organic produce. Consumers were scandalized. Their expensive organic food tainted with pesticides! The very chemicals they were trying to avoid because, as everyone knows, pesticides cause cancer! Alright now, let’s just take a deep breath here and examine what this finding by CFIA really means. First of all pesticides in the amounts found as residues on produce do not cause cancer. If they did they would not be allowed by the Pesticide Management Regulatory Agency.
PMRA is extremely safety conscious and loads of safety data are required before a pesticide is allowed to be used. Yes, some pesticides in high doses can cause cancer in test animals. But so can a host of other chemicals we are exposed to in our daily life. Starting with alcohol, a potent carcinogen. And there are many naturally occurring compounds in food that can cause cancer at some dose. Psoralens in celery, aflatoxins in various moulds and all sorts of naturally occurring compounds of arsenic, chromium and selenium cause cancer at some dose. So equating pesticides with carcinogens is incorrect. When it comes to pesticide residues the question to ask is not whether they are there or not, because with our sophisticated techniques these days we can detect unbelievably small amounts.
The question to ask is whether the residues are in violation of the maximum allowed levels, which you have to remember have a huge safety margin built in. The fact is that it is extremely rare in conventional produce to have any violation, with the vast majority of tests barely detecting any residue at all. Of course people buy organic because they don’t want any pesticide residues at all. Whether that is rational or not, organic is what they are paying for. And they may not always be getting it. The CFIA survey showed that for example some of the organic apples tested had residues of the fungicide thiabendazole to the extent of 0.03 ppm. That is an incredibly small number. It is even minute compared with the 0.4 ppm found on conventional apples, which itself is well below the safety level.
Any press report that suggests the finding of pesticides on organic produce presents a risk is misleading. But why should there be any residue on organic produce. Various reasons. Sometimes conventional produce is fraudulently sold as organic because profits are so lucrative. Sometimes pesticides may drift from a neighbouring farm. Sometimes there can be cross-contamination from conventional produce during shipping. Basically this story about pesticides being found on organic produce amounts to nothing more than a testimonial to the abilities of analytical chemists to detect vanishingly small amounts of chemicals. Remember, though, that presence of a chemical does not equate to the presence of risk. It is always a question of amount. Granted, someone who is buying organic should be getting what they are paying for, so it would be helpful to have a national organic inspection system. Right now we basically rely on an honour code when a farmer claims to be growing organic crops. That’s not good enough.
