Follow-Up Genotoxic Study: Chromosome Damage Two and Six Years after Exposure to the Prestige Oil Spill

Abstract

BackgroundThe north-west coast of Spain was heavily contaminated by the Prestige oil spill, in 2002. Individuals who participated in the clean-up tasks showed increased chromosome damage two years after exposure. Long-term clinical implications of chromosome damage are still unknown.ObjectiveTo realize a follow-up genotoxic study to detect whether the chromosome damage persisted six years after exposure to the oil.DesignFollow-up study.SettingFishermen cooperatives in coastal villages.ParticipantsLocal fishermen who were highly exposed (n = 52) and non-exposed (n = 23) to oil seven years after the spill.MeasurementsChromosome damage in circulating lymphocytes.ResultsChromosome damage in exposed individuals persists six years after oil exposure, with a similar incidence than those previously detected four years before. A surprising increase in chromosome damage in non-exposed individual was found six years after Prestige spill vs. those detected two years after the exposure.LimitationsThe sample size and the possibility of some kind of selection bias should be considered. Genotoxic results cannot be extrapolated to the approximately 300,000 individuals who participated occasionally in clean-up tasks.ConclusionThe persistence of chromosome damage detected in exposed individuals six years after oil exposure seems to indicate that the cells of the bone marrow are affected. A surprising increase in chromosome damage in non-exposed individuals detected in the follow-up study suggests an indirect exposition of these individuals to some oil compounds or to other toxic agents during the last four years. More long-term studies are needed to confirm the presence of chromosome damage in exposed and non-exposed fishermen due to the association between increased chromosomal damage and increased risk of cancer. Understanding and detecting chromosome damage is important for detecting cancer in its early stages. The present work is the first follow-up cytogenetic study carried out in lymphocytes to determine genotoxic damage evolution between two and six years after oil exposure in same individuals.

Long-Term Respiratory and Genotoxic Effects in The Prestige Oil Spill

“…There was no improvement in the pulmonary function and biological respiratory parameters after four years of follow-up in the fishermen exposed to fuel, although there was no clear data indicating that the degree of exposure was associated with the long-term effects 14 . A long-term genotoxic study, conducted in 52 exposed and 23 non-exposed individuals, showed that structural alterations remained high in exposed individuals, although the association with the exposure to the oil spill could not be substantiated because there was a relevant increase of structural alterations in nonexposed individuals 15 . Nevertheless, 2p23 and 2q23 chromosome bands were only detected in exposed individuals 16 The main results of the SEPAR-Prestige Study are summarised in table 2.…”

Human Genotoxic Study Carried Out Two Years after Oil Exposure during the Clean-up Activities Using Two Different Biomarkers

“…Moreover, due to certain volatile organic oil compounds, in particular benzene, being carcinogenic in humans [3], it is very important to determine if exposure to oil during clean-up tasks is associated with genotoxic effects in the short-(less than 12 months) and long-term (more than one year). So far, only a few human genotoxic studies in oil exposed populations have been published, most after the wreck of the Prestige [4][5][6][7][8][9][10][11][12][13][14]. In general, these studies revealed increased genomic damage in exposed individuals during the clean-up tasks [4][5][6][7][8][9][10][11].…”

“…In general, these studies revealed increased genomic damage in exposed individuals during the clean-up tasks [4][5][6][7][8][9][10][11]. Nevertheless, only two research groups have carried out long-term genotoxic studies after oil exposure to the Prestige [12][13][14][15], with conflicting results. In one group, the authors described an increase of structural chromosome alterations in highly exposed vs. non-exposed individuals two and six years after exposure [12][13][14], this follow-up study reveal that chromosome damage persisted at least for the six years.…”

“…Nevertheless, only two research groups have carried out long-term genotoxic studies after oil exposure to the Prestige [12][13][14][15], with conflicting results. In one group, the authors described an increase of structural chromosome alterations in highly exposed vs. non-exposed individuals two and six years after exposure [12][13][14], this follow-up study reveal that chromosome damage persisted at least for the six years. Yet in another group, the study detected no genotoxic effects to be present seven years after exposure using other biomarkers (comet, micronucleus and T-cell receptor mutation assays) [15].…”

“…The micronucleus test, comet assay and chromosome alterations have been the most common biomarkers to determine genetic damage in any population exposed occupationally or environmentally to genotoxic chemicals, e.g., oil exposure during clean-up tasks [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. A micronucleus is the result of chromosome breakage (acentric fragment) and/or loss (whole chromosome) caused by errors in DNA repair or in chromosome segregations not included in the main nucleus that are surrounded individually by the nuclear membrane [19].…”