Apples have been named by US-based industry analyst the Environmental Working Group (EWG) as the item of fresh produce likely to be most contaminated with pesticide residues.
The fruit topped the organisation's so-called Dirty Dozen List, which has been expanded for the second year running as part of EWG's 2013 Shopper's Guide to Pesticides in Produce, moving ahead of celery, peaches and strawberries.
Also on the list of products that EWG recommended shoppers buy organic were spinach, bell peppers, imported nectarines, cucumbers, potatoes, cherry tomatoes and chilli peppers.
EWG's Clean Fifteen list, meanwhile, identified products with what it said were the lowest traces of pesticides, including sweetcorn, onions, pineapples, avocados, cabbage, frozen peas, papayas, mangoes, asparagus, aubergines, kiwifruit, grapefruit, cantaloupe melons, sweet potatoes and mushrooms.
"When given a choice, more consumers are choosing organic fruits and vegetables or using EWG's Shopper's Guide to find an easy affordable way to avoid toxic chemicals," said Sonya Lunder, senior analyst at EWG. "They want to eat a diet rich in fruits and vegetables without eating too many pesticides. And they want to support local farms and agriculture that is better for the environment."
Now in its ninth year, the Shopper's Guide to Pesticides in Produce measured pesticide contamination on 48 popular fruits and vegetables, based on an analysis of more than 28,000 samples tested by the US Department of Agriculture and federal Food and Drug Administration.
EWG researchers compiled the lists from pesticide residue test data made public by the two agencies earlier this year, employing six different measures.
According to EWG, government scientists washed or peeled samples before testing them, meaning their measurements reflected the likely pesticide load to which a consumer would be exposed.