In recent years, due to resistance of pests, changes of pesticides market, and other reasons, mixed pesticides were widely used, such as binary pesticide mixtures (He, 2001). In this study, we have found the blending use of PYR with PYR, OP with OP, OP with PYR in vegetables planting. Up to now, there are no mixed pesticide standards of hygiene by China, however, the prevention and detection studies have been reported (Wu et al., 2007). At present, it is difficult to achieve rational use, mainly due to the mixed pesticides using the common name or/and label is unclear in the market. Furthermore, inadequate supervision by relevant departments and the producers' lack of knowledge in using pesticides cause excessive pesticide spraying and residues in vegetable products. In this case, further limitations and/or bans should be sought, along with alternative solutions that are safer and non-toxic to the environment and humans. Studies on the occurrence, fate and impact of pesticides on public health and ecosystems are needed.
4. Conclusion
From 2010 to 2013, a total of 506 vegetable samples were collected from local agricultural markets, supermarkets and hypermarkets. The results indicated that pesticide residue accumulation needs more attention because most of the pesticides found could cause considerable health problems for both producers and the public. Therefore, governmental departments should strengthen their regular supervision of the pesticide levels of market foods and promote education on the potential risks and the safe use of pesticides. This study may serve as a basis for relevant government departments in China to take proper measures to ensure that these pollutants of vegetables are within the permissible limits for sale to subsequently minimise health risks.