Pesticides in China
Hi - I am 6 months pregnant and concerned about the level of pesticides I could be ingesting here in China that may affect my baby's development. In particular, I just read about chlorpyrifos potentially impacting my baby's brain development. Do you know if this is used prevalently here in China? If so, what can I do other than to avoid all food? It's impossible to import everything I eat and completely avoid eating out. Thanks
Because it was quite complex, we asked two experts for help with this answer.
Our pollution expert, Louie Cheng:
Chlorpyrifos is a chemical used in pesticides classified by the WHO and the EPA as Moderately Toxic with reproductive and developmental toxicity and potentially carcinogenic properties -- particularly on fetuses and young children. It was banned from residential use in the US in 2001. It is still widely used in agriculture, and is still marketed for home use in developing countries.
It is mostly used for insect control on crops but also for mosquito and cockroach control. Very widespread. Even in the US, a study by the US Center for Diseases Control (CDC), found that a metabolite specific to chlorpyrifos was found in the urine of 91% of subjects tested. Chlorpyrifos has also been found in the air by air testing done by the California Air Resources Board. I am checking with my lab to see if we are able to test for chlorpyrifos, but I would guess that it would be in the air here as well.
Is it used in China? China is the largest global producer of chlorpyrifos. In 2010, China established a Chlorpyrifos Consortium with over 20 producers with the stated intent of "extending the lifecycle of the product and improving the competitiveness of the pesticide in the market." So, it's not banned and I did find some Chinese suppliers marketing to residential use. China has one of the world's highest rates of chemical fertilizer use per hectare, and Chinese farmers use many highly toxic pesticides, including some that are banned in the United States. Farm chemicals are sometimes mislabeled. The Chinese government is tackling this problem by encouraging farmers to buy agricultural chemicals only from approved outlets. Some farmers have little understanding of correct chemical use; for example, they may fail to wait the prescribed number of days between the last application of a pesticide and harvest, resulting in excessive residues in the harvested product. For more on why pesticide use is so high among produce in China (including the banning of frozen spinach exports to Japan in 2001-03), read this good article.
A Feb, 2012 study by the Chinese Academy of Sciences found that rice and cabbage residue by the average Chinese resident in Beijing represented 7% and 13% of allowable chlorpyrifos daily intake and concluded that "The application of chlorpyrifos at the recommended dose on rice and cabbage is unlikely to pose any public health issues". However, I wasn't able to find the standards they used, and it is very possible that the standards are less rigorous than international standards (like that of maximum allowable lead levels, which are 10x higher here than in the US).
"Tesco produce in China unsafe for three years now" -- Greenpeace currently has a public interest lawsuit filed against Tesco in China due to high levels of pesticides, including chlorpyrifos, which were detected during 4 rounds of testing conducted from 2009-12. According to Greenpeace, leeks had chlorpyrifos levels twice that of Chinese standards.
What are the standards? The EPA sets a very stringent daily exposure limit of 30 nanograms per kg of bodyweight. Australia has set this at 3000 ng and the WHO at 10,000 ng.
What can you do to minimize exposure? Eating verified organic produce will reduce intake. Primary route will be through eating treated produce. According to a 2008 CDC study, levels of chlorpyrifos and malathion in the urine of children studied dropped to negligible levels after switching from regular store-bought produce to organic produce for a 5 day intervention period. To be fair, chlorpyrifos is used for agricultural pesticidal use in the US and nearly 100 other countries, including in Europe, so this is not unique to China. Spinach and leeks in particular have been found in numerous studies to have high levels of contamination, so getting organically grown stock is a good idea.
Also, exposure comes from breathing in areas where chlorpyrifos is used as pesticides. Ask your management what they use for insecticide in your compound. Do not send me a photo of the Chinese label, but get the trade name and do a web search of that against "chlorpyrifos". If they are "Dursban" "Lorsban" or "Renoban" or you get a hit against chlorpyrifos, share this information with your compound and ask them to find an alternative. Chances are they simply don't know. Then keep following up with them to ensure they are using something different, or you can also contact us to come and do a testing of air in the compound to audit the safety.
Saeid Mirafzali MD MHSA, Internal Medicine Physician:
I understand your concern. However, I think it's important to gain some perspective rather than taking, what sounds like, extreme measures. A few things to consider :
1) While this pesticide is used in China, it and others are also used in many Western countries as well.
2) Both perceived and real risks with regards to food safety exist in ALL countries. These real risks have been around for decades but hadn't received the publicity.
3) Shopping imported and avoiding eating out doesn't guarantee improved safety, unless you know where the source of the individual ingredients in the food you eat. It seems the most logical approach is to make responsible efforts to eat as much organic based products as possible while not getting overly stressed about products that you enjoy but cannot source organically.
4) No one can avoid all harmful environmental exposures. Therefore, it's important to focus on aspects of our lives that we can change to promote greater resiliency against environmental threats ( regular exercise, balanced diets, stress reduction, positive thinking, maintaining close and healthy social relationships, etc). The beneficial effects of these long- term should not be underestimated.