Follow-up study of genotoxic effects in individuals exposed to oil from the tanker Prestige, seven years after the accident.

The accident with the oil tanker Prestige in November 2002 resulted in a major spill of about 63,000 tons of heavy fuel oil. More than 300,000 people participated in the clean-up activities, which lasted for up to 10 months. Previous studies reported increases in genotoxicity endpoints in individuals exposed to Prestige oil, both at the moment of exposure [DNA breakage, micronuclei (MN), sister chromatid exchange] and two years later (chromosomal aberrations). In this work we carried out for the first time the follow-up of genotoxic effects in subjects exposed to an oil spill seven years after the exposure. The main objective was to determine the possible persistence of genotoxic damage in individuals exposed to Prestige oil seven years after the accident. The exposed group was composed of 54 residents of Galician villages in Spain that were heavily affected by the spill. This group was involved in clean-up labor for at least two months in the period November 2002-September 2003. They were compared with 50 matched controls. Primary DNA damage was evaluated by the comet assay, mutagenicity by the T-cell receptor (TCR) mutation assay, and MN frequency was determined both by the cytokinesis-block test and by flow cytometry. The results obtained showed no significant differences between the exposed and the controls in the comet assay, the TCR mutation assay and the cytokinesis-block MN test. An unexpected and significant decrease was observed in the exposed group for the results of the MN test evaluated by flow cytometry, probably influenced by modifying factors - other than age, sex and smoking - not considered in this study. Our results show no evidence of the persistence of genotoxic damage in individuals exposed to Prestige oil seven years later. Nevertheless, the need to plan biomonitoring studies on people participating in clean-up activities in case a new oil spill occurs should be established.

Endocrine and immunological parameters in individuals involved in Prestige spill cleanup tasks seven years after the exposure.

In November 2002 the oil tanker Prestige spilled 63,000tonnes of heavy oil off the northwest coast of Spain, impacting more than 1000km of coastline. A general concern led to a huge mobilization of human and technical resources, and more than 300,000 people participated in cleanup activities, which lasted up to 10months. Some endocrine and immunological alterations were reported in Prestige oil exposed subjects for several months. Therefore, the objective of this study was to evaluate if these alterations are still present seven years after the exposure. Fifty-four individuals exposed for at least 2months were compared to 50 matched referents. Prolactin and cortisol plasma concentrations, percentages of lymphocyte subsets (CD3(+), CD4(+), CD8(+), CD19(+), and CD56(+)16(+)), plasma levels of circulating cytokines (interleukin (IL) 2, IL4, IL6, IL10, tumour necrosis factor α, and interferon γ), and serum concentrations of neopterin, tryptophan and kynurenine were determined in peripheral blood samples. Results showed significant differences in exposed individuals vs. referents only in cortisol (increase), kynurenine and %CD16(+)56(+) lymphocytes (both decrease). Time of exposure to the oil or using protective clothes did not influence the results, but effect of using protective mask was observed on neopterin, %CD8(+), CD4(+)/CD8(+) ratio and IL4. Surveillance of the exposed individuals for early detection of possible health problems related to the endocrine or immunological systems is recommended.