There is a scare among consumers that contaminants in produce can increase likelihood of cancer–this drives an increasing demand for organically grown food which is thought to be healthier. Relevant peer-reviewed studies are scarce, and though there is some evidence organic food is less contaminated, there is no clear conclusion in published literature.
Organically grown produce does appear to be less contaminated. For example leafy, root, and tuber organic vegetables show lower nitrate content and organic fruit contain fewer agrochemical residues. However, in both cases the contamination is far below acceptable limits, and links between agrochemical residues and nitrates with cancer incidence are not clearly verified. Nonetheless concerns arise because contaminant detection is increasing with time,.
A study published a little over a the British Journal of Cancer found that among 623, 080 middle-aged women living in the UK followed for over 9 years cancer incidence had no ties to eating organically grown produce, except in the case of non-Hodgkin Lymphoma, which was inconclusive. The findings may be dismissed by overzealous academics unfamiliar with cancer lifestyle research since it lacks experimental methodology, but experiments on this scale are infeasible (imagine conducting double blind feeding studies on 600k women over 10 years!).