Impact of crude oil on yield and phytochemical composition of selected green leafy vegetables

Total petroleum hydrocarbons (TPH) cleanup standards, intervention and/or target values, are designed to effectively manage introduction of toxic petroleum hydrocarbons into the environment. This research assessed the impact of some crude oil remediation intervention values (CRIV), involving sublethal concentrations of crude oil, on yield and phytochemical contents of kale (Brassica oleracea L.) and lettuce (Lactuca sativa L.). Crude oil contamination within the range examined did not affect emergence; yield and phytochemical distributions were affected at some levels of contamination, particularly 10000 mg·kg−1 TPH. There is the potential of TPH to moderate effects of crude oil at 10000 mg·kg−1 to enhance contents of some phenolics and organic acids in green leafy vegetables, but it causes accelerated maturity and leaf senescence. Use of CRIV below 10000 mg·kg−1 TPH appears to be effective.