Kale was ranked third in the list of 12 fruits and vegetables with the most pesticide residues, the Environmental Working Group announced this week.
The list was topped by strawberries and spinach, followed by kale which can be contaminated by cancer-causing pesticides although being known as a source of vitamins and other nutrients.
The non-profit environmental group has been ranking pesticide contamination in popular fruits and vegetables for its Shopper's Guide on a yearly basis since 2004, issuing the "dirty dozen" and "clean fifteen" lists.
Results revealed that 92% of the samples of conventionally grown Kale came positive for two or more pesticide residues, and a single sample of kale sometimes contained as many as 18 different pesticide residues.
The most widespread pesticide detected was Dacthal, also known as DCPA, and has been identified as a potential cancer-causing agent which Europe prohibited in 2009.
The 2019 "Dirty Dozen" list includes: strawberries, spinach, kale, nectarines, apples, grapes, peaches, cherries, pears, tomatoes, celery and potatoes.
Avocados, sweet corn, pineapples, frozen sweet peas and onions featured in the "Clean Fifteen" list, being considered as the safest in terms of pesticide contamination.