Clean-up Workers Research Articles

Chronic Lymphocytic Leukemia in Chornobyl Cleanup Workers.

This paper describes the chronic lymphocytic leukemia (CLL) incidence in a cohort of 110,645 (enlarged later to 152,520) male Ukrainian cleanup workers of the Chornobyl (Chernobyl) accident who were exposed to a range of radiation doses over the 1986-1990 time period. The standardized incidence rates are presented for a 27-y period after the exposure. For 2007-2012 period, the authors have identified the incident CLL cases in an enlarged cohort of 152,520 persons by linkage of the cohort file with the Ukrainian National Cancer Registry (NCRU). CLL data for the previous period (1987-2006) were identified in a frame of the Ukrainian-American leukemia study in the original cohort of 110,645 male clean-up workers. A significant CLL incidence excess was shown for the entire study period 1987-2012, with more prominent levels for the earliest years (1987-1996) when the standardized incidence rate (SIR) value was estimated to be 3.61 with 95% confidence interval from 2.32 to 4.91. In 2007-2012, the CLL incidence decreased substantially but still exceeded the national level although not significantly. In parallel, the several studies were performed at the National Research Center for Radiation Medicine (NRCRM) to explore if any clinical and cytogenetic features of CLL existed in the clean-up workers. The clinical study included 80 exposed and 70 unexposed CLL cases. Among the major clinical differences of the CLL course in the clean-up workers were a shorter period of white blood cells (WBC) doubling (10.7 vs. 18.0; p<0.001), frequent infectious episodes, lymphoadenopathy and hepatosplenomegaly (37 vs. 16), higher expression for CD38, and lower expression for ZAP-70 antigen.

DIRECT AND CROOKED DEMOCRACY

DIRECT AND CROOKED DEMOCRACY

30years After the Chernobyl Nuclear Accident: Time for Reflection and Re-evaluation of Current Disaster Preparedness Plans.

It has been 30years since the worst accident in the history of the nuclear era occurred at the Chernobyl power plant in Ukraine close to densely populated urban areas. To date, epidemiological studies reported increased long-term risks of leukemia, cardiovascular diseases, and cataracts among cleanup workers and of thyroid cancer and non-malignant diseases in those exposed as children and adolescents. Mental health effects were the most significant public health consequence of the accident in the three most contaminated countries of Ukraine, Belarus, and the Russian Federation. Timely and clear communication with affected populations emerged as one of the main lessons in the aftermath of the Chernobyl nuclear accident.

Health effects of non-occupational exposure to oil extraction.

Oil extraction may cause extensive environmental impact that can affect health of populations living in surrounding areas. Large populations are potentially exposed to oil extraction related contamination through residence in areas where oil extraction is conducted, especially in low and middle income countries (LMICs). Health effects among people residentially exposed to upstream oil industry contaminants have been poorly studied. Health effects of exposure to oil related contamination have been mainly studied among cleanup workers after oil spills from tankers or offshore platforms.In this paper we aim to identify the type and extension of residential exposures related to oil extraction activities and to comment on the few health studies available. We estimated that 638 million persons in LMICs inhabit rural areas close to conventional oil reservoirs. It is relevant to specifically study people residentially exposed to upstream oil industry for the following reasons: First, persons are exposed during long periods of time to oil related contamination. Second, routes of exposure differ between workers and people living close to oil fields, who can be exposed by ingestion of contaminated waters/foods and by dermal contact with contaminated water and/or land during daily activities (e.g. bathing, agricultural activities, etc.). Third, individuals potentially more susceptible to the effect of oil related contamination and not normally occupationally exposed, such as infants, children, pregnant women, elderly or people with previous health conditions, are also exposed.There are few papers studying the potential health effects of residential exposure to oil related contamination, and most of them share important limitations. There is a need for more research through the conduct of methodologically robust studies in exposed populations worldwide. Despite the difficulties in the conduct of studies in remote areas, novel approaches, such as measurement of individual exposure using biomarkers of exposure and effect, should be used. These studies should be promoted to understand the health risks associated to residential exposure to oil related contamination, support effective control policies to avoid such contamination and to sustain public health recommendations and policies to avoid exposure in already contaminated areas.

Development of Occupational Health Measures for the National Health Security Preparedness Index.

Development of Occupational Health Measures for the National Health Security Preparedness Index.

Gene regulation of telomere length in human peripheral blood lymphocytes in early and remote perods after irradiation

Radiation-associated violations of gene regulation of lymphocytes telomere length in early and late period after exposure are investigated. In Chernobyl clean-up workers in the range of doses more than 500 mSv was set reduction of relative telomere length and imbalance in TERF1, TERF2 gene expression on the background of p53-mediated activation of telomerase activity. The early period after professional exposure in“Shelter” object characterized by impairment of protective function of telomeres

Clinical characteristics of chronic lymphocytic leukemia occurring in chornobyl cleanup workers.

The recently demonstrated radiation-induction of chronic lymphocytic leukemia (CLL) raises the question as to whether the amount of radiation exposure influences any of the clinical characteristics of the disease. We evaluated the relationship between bone marrow radiation doses and clinical characteristics and survival of 79 CLL cases diagnosed during 1986-2006 in a cohort of 110 645 male workers who participated in the cleanup work of the Chornobyl nuclear accident in Ukraine in 1986. All diagnoses were confirmed by an independent International Hematology Panel. Patients were followed up to the date of death or end of follow-up on 31 October 2010. The median age at diagnosis was 57 years. Median bone marrow dose was 22.6 milligray (mGy) and was not associated with time between exposure and clinical diagnosis of CLL (latent period), age, peripheral blood lymphocyte count or clinical stage of disease in univariate and multivariate analyses. Latent period was significantly shorter among those older at first exposure, smokers and those with higher frequency of visits to the doctor prior to diagnosis. A significant increase in the risk of death with increasing radiation dose was observed (p = 0.03, hazard ratio = 2.38, 95% confidence interval: 1.11,5.08 comparing those with doses ≥22 mGy to doses <22 mGy). After adjustment for radiation dose, survival of CLL cases was significantly shorter among those with younger age at first exposure, higher peripheral blood lymphocyte count, more advanced clinical stage of disease and older age at diagnosis (all p < 0.05). This is the first study to examine association between bone marrow radiation doses from the Chornobyl accident and clinical manifestations of the CLL in Chornobyl cleanup workers. The current study provides new evidence on the association of radiation dose and younger age at first radiation exposure at Chornobyl with shorter survival after diagnosis. Future studies are necessary with more cases in order to improve the statistical power of these analyses and to determine their significance. Copyright © 2016 John Wiley & Sons, Ltd.

Vestibular and acustic dysfunctions in clean-up workers of Chornobyl accident (30 years of follow-up)

The objective of the work was to study the clinical and electrophysiological disorders in vestibular and acustic dysfunctions in clean up workers of Chornobyl accident depending on the dose and duration of action of ion izing radiation, the peculiarities of determined effects for 30 years after the accident. The standard clinical and electrophysiological examinations of vestibular and acoustic ana lyzers functions were conducted in 7812 males' clean up workers including 325 persons selected for prolonged stud ies in 1986 2015. The mathematical methods of analysis were carried out using the software package SYSTAT, EPICURE and EGRET. Vestibular dysfunction and acoustic dysfunction according the central type of progressive development of inhibitory processes in the brain stem, subcortical and cortical structures of vestibular and acoustic analyzers were determined. The dependence of changes in these structures on the dose and duration of ionizing radiation effect was defined. The regularities of determined radiation effects in correlation with the formation of organic cerebrovascu lar pathology in the clean up workers in remote post accident years that are consistent with neurophysiological, MRI and other examinations confirmed with correlation analysis were established. It was registered that the vestibular and acoustic dysfunctions in the clean up workers were manifest ed by the clinical and electrophysiological changes at the level of central structures in the studied analyzers, which indicate the parallelism of common mechanism of determined radiation effects already at a dose of 0.20 Gy, and also their dose dependency in dynamics of 30 post accidental years. It was established that vestibular dysfunction in the clean up workers is clinically early manifested, and the electroacoustic and electrophysiological changes in a case of normal hearing are evidence of preclinical inhibitory processes in the brain stem, subcortical and cortical structures of acoustic analyzer in the early post accident years. The features of the clinical course of vestibular and acoustic dysfunctions in long term monitoring of short term effects of ionizing radiation in high doses in the group of the clean up workers who have acute radiation sickness, and the manifestation of change is greater and accelerated in time under long term IR effect, than the relatively short term ones in similar small doses in distant years. Significant increase of hearing disorders by type of presbyacuzis precox in the respective age categories, which is one of the symptoms of their premature their aging was studied in clean up workers.

Microcirculation violations of the conjunctiva in clean-up workers of the Chornobyl NPP accident

Explore hemomicrocirculation changes after radiation exposure depending of irradiation dose in dynam ics. The research conducted on 470 clean up workers of the Chornobyl NPP accident. After 10-15 years after radiation exposure examined 450 Chornobyl clean up workers in age of 28 to 65 years. The con trol group consisted of 110 industrial workers who had not a contact of IR. In 22 years after radiation exposure sep arately examined 20 randomly selected Chornobyl clean up workers accident. The microcirculation state examine by the vessels biomicroscopy of the bulbar conjunctiva. The statistical analysis of the results of the study included the determination of the t coefficient (Student's), correlation coefficient and its error. The research of the state of microcirculation in the conjunctiva revealed the presence of significant irreg ularities in exposure persons in the period of 10-15 years after radiation exposure. The dependence educed of the degree and frequency of pathology of the microvessels of dose accumulation. In 22 years after radiation exposure hemomicrocirculation violations remained widespread, a large proportion was vascular and perivascular changes. Established that the dose dependences for changes of the microcirculation in the remote period in participants work at Chornobyl in 1986 save. It is shown that the appearance of the significant violations of microcirculation state in the conjunc tiva observed in exposed persons in the period from 10 to 15 years after radiation exposure. In 22 years after radi ation exposure dose dependence hemomicrocirculation violations remained widespread, and clinical features are preserved.

Social and psychological state of the Chornobyl clean/up workers. Risk factors for negative changes

To study social and psychological state of the Chornobyl cleanup workers 1986-1987, and to determine regularities of changes and dangerous risk factors. On the basis of Polyclinic of Radiation Registry, NRCRM, we conducted sample epidemiolog ical study of social and psychological state of the Chornobyl clean up workers 1986-1987. We used method of inter viewing based on «questionnaire», specially developed for this purpose. The study was conducted in October 2013 - May 2015. The sample numbered 235 males aged 18-50 at the time of the accident. Their average age was (31.3 ± 5.3) years at the time of the accident and (58.9 ± 5.3) at the time of survey. The results revealed that the Chornobyl nuclear accident and its consequences caused strong social and psychological stress among clean up workers 1986-1987. We have identified a set of factors closely related to the Chornobyl accident, they have caused a sustainable development of mental syndrome - «Anxiety about their own health and the health of family members, especially children». The other set of stressors which are not closely relat ed to the Chornobyl accident but are the result of the social and economic, social and political situation in the coun try. However the former was found to be the cause of such a psychological state as «dissatisfaction with the com pleteness and quality of life». Social and psychological state of the Chornobyl clean up workers 1986-1987 is estimated as «poor» and it integrally can be characterized as a state of chronic psychosocial stress. Mental syndrome «Anxiety about per sonal health and the health of family members» and psychological syndrome «Dissatisfaction with living condi tions» are main consequences of this state. We identified the main stressors closely related to the consequences of the Chornobyl accident as well as those that are not related to the accident but affect profoundly the level of men tal, social and physical well being. Results of the research are of great importance in organization and provision of social, medical and antiradiation protection of population under emergency situations involving radiation exposure. Key words: Chornobyl accident, clean up workers, social and psychological state, risk factors.

Overexpression of TP53, TP53I3and BIRC5, alterations of gene regulation of apoptosis and aging of human immune cells in a remote period after radiation exposure

To identify a contributive role of changes in gene regulation of apoptosis and telomere length at tran scriptional and translational levels to the formation of radiation induced effects in immune system. Study groups included 310 Chornobyl (Chornobyl) cleanup workers (dose of external expo sure (360.82 ± 32.3) mSv; age 58.9 ± 0.6 (M ± SD) years) and control (n = 77; age (52.9 ± 0.64) (M ± SD) years). Expression of CD95, phosphatidylserine receptors, bcl2 and p53 proteins was studied by flow cytometry; the relative expression (RQ) of BAX, BIRC5, FASLG, MADD, MAPK14, TP53, TP53I3, TERT, TERF1, TERF2 genes was performed using 7900 HT Fast RT PCR System and TagMan technology. Relative telomere length (RTL) was quantified by flow FISH assay. Dose dependent deregulation of apoptosis was shown at transcriptional level (TP53, TP53 I3, BAX, BIRC5, FASL genes) and translational level (bcl 2 and p53 proteins) with blocking entry to apoptosis, dose dependent activation of anti apoptotic proteins and TP53 mediated expression of genes inhibitors of apoptosis. After exposure below 100 mSv a decrease in TERT gene RQ was associated with shortened telomeres, after exposure to doses over 500 mSv the TERT RQ and RTL increase were associated with imbalance in TERF1 and TERF2 genes expression. Our study demonstrates a presence of subsequent changes in gene expression, regulatory proteins pres entation, telomere length and distribution of cells by the stages of apoptosis in a late period after radiation expo sure from low dose range to doses over 500 mSv. Results of the study contribute to the basic concepts on the late biological effects in immune system.

Health Risks to Ecological Workers on Contaminated Sites - the Department of Energy as a Case Study.

At most contaminated sites the risk to workers focuses on those 'hazardous waste workers' directly exposed to chemicals or radionuclides, and to the elaborate approaches implemented to protecting their health and safety. Ecological workers generally are not considered. To explore the risks to the health and safety of ecological workers on sites with potential chemical and radiological exposures before, during or after remediation of contamination. To use the U.S. Department of Energy as a case study, and to develop concepts that apply generally to sites contaminated with hazardous or nuclear wastes. Develop categories of ecological workers, describe their usual jobs, and provide information on the kinds of risks they face. Ecological activities include continued surveillance and monitoring work on any sites with residual contamination, subject to institutional controls and engineered barriers following closure as well as the restoration. The categories of ecological workers and their tasks include 1) Ecological characterization, mapping and monitoring, 2) biodiversity studies, 2) Contaminant fate and transport, 3) On-going industrial activities 4) Remediation activities (environmental management), 5) Environmental restoration, 6) Post-cleanup surveillance and monitoring, and 7) Post-closure future site activities. There are a set of functional activities that can occur with different frequencies and intensities, including visual inspection, collecting biological samples, collecting media physical samples, collecting biological debris, restoration planting, and maintaining ecosystems. Ecological workers face different exposures and risks than other environmental cleanup workers. Many of their tasks mimic shift work with long hours leading to fatigue, and they are exposed to biological as well as chemical/radiological hazards. DOE and other entities need to examine the risks to ecological workers on site with an eye to risk reduction.

The Chernobyl – Thirty Years After The Post – Accidental Radiological – Hygienic and Medical Consequences

As the result of the Chernobyl NPP accident more than 200 thousand square kilometers of the European territories were contaminated by Cs-137 in the amount of above 37 kBq/m2 (1 Ci/km2 ). Belorussia, Russia and Ukraine amount up to 70% of this entire affected area. More than 600 000 people were engaged in the accidental cleanup operations, 340000 were evacuated or relocated within 1986-1991. The early stage evacuation efficacy is confirmed by the absence of acute radiation syndrome among the population and by the prevented collective dose which amounts to no less than 10 000 man/Sv. The effective measure to reduce the internal radiation dose to the population at the early accidental stage was introduction of maximum tentative permissive levels of radionuclide content in the foodstuffs.Among the identified post -accident medical consequences of the Chernobyl is the radiation syndrome found in 134 emergency cleanup workers within the first 24 hours of the accident’s development. Out of that number, 28 people died within the first four months, 19 people died before 2006. The accident’s liquidators developed radiation -induced leukemia ( the attributive risk value is 45-60% ). People exposed to high radiation doses display the statistically significant 18% morbidity increase of all types of solid cancers at the doses above 150 mSv. There is the statistically significant information indicating the increased amount of thyroid cancer morbidity among those who were just children and teenagers at the time of the accident. The adverse psychological consequences are accounted for not just the fear of overexposure but also for the disturbance of the habitual lifestyle especially mindful of the forced relocation.The longterm protection measures, radionuclide decay and selfcleaning of the contaminated areas resulted in the drastic reduction of the population dose in the radioactively contaminated territories. In 2015, only in some settlements of the Briansk Region’s the mean annual effective dose to the population exceeds 1 mSv. Presently the major goal is to transfer to normal human life with the change of the legal status of radioactively contaminated settlements in which the radiation situation is back to normal.The article provides the comparative data on the Chernobyl and the Fukushima - 1 accidental consequences and emphasizes the necessity of retaining the Chernobyl experience because the rapid advancement of the atomic energy around the world makes the mitigation of the accident’s consequences a truly international mission.

Hypermethylation of gene promoters in peripheral blood leukocytes in humans long term after radiation exposure

Some human genes known to undergo age-related promoter hypermethylation. These epigenetic modifications are similar to those occurring in the course of certain diseases, e.g. some types of cancer, which in turn may also associate with age. Given external genotoxic factors may additionally contribute to hypermethylation, this study was designed to analyzes, using methylation-sensitive polymerase chain reaction (PCR), the CpG island hypermethylation in RASSF1A, CDKN2A (including p16/INK4A and p14/ARF) and GSTP1 promoters in peripheral blood leukocytes of individuals exposed to ionizing radiation long time ago. One hundred and twenty-four irradiated subjects (24–77 years old at sampling: 83 Chernobyl Nuclear Power Plant clean-up workers, 21 nuclear workers, 20 residents of territories with radioactive contamination) and 208 unirradiated volunteers (19–77 years old at sampling) were enrolled. In addition, 74 non-exposed offspring (2–51 years old at sampling) born to irradiated parents were examined. The frequency of individuals displaying promoter methylation of at least one gene in exposed group was significantly higher as compared to the control group (OR=5.44, 95% CI=2.62–11.76, p=3.9×10−7). No significant difference was found between the frequency of subjects with the revealed promoter methylation in the group of offspring born to irradiated parents and in the control group. The increase in the number of methylated loci of RASSF1A and p14/ARF was associated with age (β=0.242; p=1.7×10−5). In contrast, hypermethylation of p16/INK4A and GSTP1 genes correlated with the fact of radiation exposure only (β=0.290; p=1.7×10−7). The latter finding demonstrates that methylation changes in blood leukocytes of healthy subjects exposed to radiation resemble those reported in human malignancies. Additional studies are required to identify the dose-response of epigenetic markers specifically associating with radiation-induced premature aging and/or with the development of age-associated cancer and non-cancer diseases.

Dosimetry Support of the Ukrainian-American Case-control Study of Leukemia and Related Disorders Among Chornobyl Cleanup Workers.

This paper describes dose reconstruction for a joint Ukrainian-American case-control study of leukemia that was conducted in a cohort of 110,645 male Ukrainian cleanup workers of the Chornobyl (Chernobyl) accident who were exposed to various radiation doses over the 1986-1990 time period. Individual bone-marrow doses due to external irradiation along with respective uncertainty distributions were calculated for 1,000 study subjects using the RADRUE method, which employed personal cleanup history data collected in the course of an interview with the subject himself if he was alive or with two proxies if he was deceased. The central estimates of the bone-marrow dose distributions range from 3.7 × 10(-5) to 3,260 mGy, with an arithmetic mean of 92 mGy. The uncertainties in the individual stochastic dose estimates can be approximated by lognormal distributions; the average geometric standard deviation is 2.0.

Mental health and alcohol problems among Estonian cleanup workers 24 years after the Chernobyl accident.

To study the long-term mental health consequences of the 1986 Chernobyl nuclear accident among cleanup workers from Estonia. In 2010, 614 Estonian Chernobyl cleanup workers and 706 geographically and age-matched population-based controls completed a mail survey that included self-rated health, the Posttraumatic Stress Disorder Checklist (PCL), alcohol symptoms (AUDIT), and scales measuring depressive, anxiety, agoraphobia, fatigue, insomnia, and somatization symptoms. Respondents were dichotomized into high (top quartile) and low symptom groups on each measure. Logistic regression analysis detected significant differences between cleanup workers and controls on all measures even after adjustment for ethnicity, education, marital status, and employment status. The strongest difference was found for somatization, with cleanup workers being three times more likely than controls to score in the top quartile (OR = 3.28, 95% CI 2.39-4.52), whereas for alcohol problems the difference was half as large (OR = 1.52, 95% CI 1.16-1.99). Among cleanup workers, arrival at Chernobyl in 1986 (vs. later) was associated with sleep problems, somatization, and symptoms of agoraphobia. The toll of cleanup work was evident 24 years after the Chernobyl accident among Estonian cleanup workers indicating the need for focused mental health interventions.

Myelodysplastic syndromes in Chernobyl clean-up workers.

The studies of the recent decades posed the question of the association between radiation exposure and myelodysplastic syndromes (MDS). This association has been proved in secondary MDS originating upon exposure to chemotherapeutics and/or radiation therapy. The long-term study in Japanese atomic (A)-bomb survivors demonstrated the significant linear dose-response for MDS confirming the link between radiation exposure and this form of hematopoietic malignancies. All these findings provide the strong basis for studying MDS in the persons exposed to radiation following the Chernobyl disaster, especially those in the cohort of Chernobyl clean-up workers of 1986-1987. The data on MDS among Chernobyl clean-up workers (1986-1987) diagnosed in 1996-2012 at the reference laboratory of RE Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology are summarized. MDS cases were diagnosed in 23 persons (21 males and 2 females) having been exposed to radiation as clean-up workers of 1986-1987. Refractory anemia (RA) has been detected in 13, refractory anemia with ring sideroblasts (RARS)-in 2, and refractory anemia with excess blasts (RAEB)-in 8 patients. The median age of those MDS patients was 62.0years. In addition, 5 cases of chronic myelomonocytic leukemia (CMML) were recorded in the group of Chernobyl clean-up workers with the median time of 14.8years from 1986-1987 to diagnosis. The association between radiation exposure and MDS is discussed. The suggested life-long risk for myelodysplastic syndromes among A-bomb survivors in Japan highlights the importance of the continuing follow-up studies in the affected populations in the post-Chernobyl period.

Non-radiation risk factors for leukemia: A case-control study among chornobyl cleanup workers in Ukraine

BackgroundOccupational and environmental exposure to chemicals such as benzene has been linked to increased risk of leukemia. Cigarette smoking and alcohol consumption have also been found to affect leukemia risk. Previous analyses in a large cohort of Chornobyl clean-up workers in Ukraine found significant radiation-related increased risk for all leukemia types. We investigated the potential for additional effects of occupational and lifestyle factors on leukemia risk in this radiation-exposed cohort. MethodsIn a case-control study of chronic lymphocytic and other leukemias among Chornobyl cleanup workers, we collected data on a range of non-radiation exposures. We evaluated these and other potential risk factors in analyses adjusting for estimated bone marrow radiation dose. We calculated Odds Ratios and 95% Confidence Intervals in relation to lifestyle factors and occupational hazards. ResultsAfter adjusting for radiation, we found no clear association of leukemia risk with smoking or alcohol but identified a two-fold elevated risk for non-CLL leukemia with occupational exposure to petroleum (OR=2.28; 95% Confidence Interval 1.13, 6.79). Risks were particularly high for myeloid leukemias. No associations with risk factors other than radiation were found for chronic lymphocytic leukemia. ConclusionsThese data – the first from a working population in Ukraine – add to evidence from several previous reports of excess leukemia morbidity in groups exposed environmentally or occupationally to petroleum or its products.

OVERVIEW ON ASSOCIATION OF DIFFERENT TYPES OF LEUKEMIAS WITH RADIATION EXPOSURE

Exposure to ionizing radiation is associated with increasing risk of various types of hematological malignancies. The results of major studies on association of leukemias and radiation exposure of large populations in Japan and in Ukraine are analyzed. The patterns of different types of leukemia in 295 Chernobyl clean-up workers diagnosed according to the criteria of up-to-date World Health Organization classification within 10-25 years following Chernobyl catastrophe are summarized. In fact, a broad spectrum of radiation-related hematological malignancies has been revealed both in Life Span Study in Japan and in study of Chernobyl clean-up workers in Ukraine. The importance of the precise diagnosis of tumors of hematopoietic and lymphoid tissues according to up-to-date classifications for elucidating the role of radiation as a causative factor of leukemias is emphasized. Such studies are of high importance since according to the recent findings, radiation-associated excess risks of several types of leukemias seem to persist throughout the follow-up period up to 55 years after the radiation exposure.

Concentrations in human blood of petroleum hydrocarbons associated with the BP/Deepwater Horizon oil spill, Gulf of Mexico.

During/after the BP/Deepwater Horizon oil spill, cleanup workers, fisherpersons, SCUBA divers, and coastal residents were exposed to crude oil and dispersants. These people experienced acute physiological and behavioral symptoms and consulted a physician. They were diagnosed with petroleum hydrocarbon poisoning and had blood analyses analyzed for volatile organic compounds; samples were drawn 5-19 months after the spill had been capped. We examined the petroleum hydrocarbon concentrations in the blood. The aromatic compounds m,p-xylene, toluene, ethylbenzene, benzene, o-xylene, and styrene, and the alkanes hexane, 3-methylpentane, 2-methylpentane, and iso-octane were detected. Concentrations of the first four aromatics were not significantly different from US National Health and Nutritional Examination Survey/US National Institute of Standards and Technology 95th percentiles, indicating high concentrations of contaminants. The other two aromatics and the alkanes yielded equivocal results or significantly low concentrations. The data suggest that single-ring aromatic compounds are more persistent in the blood than alkanes and may be responsible for the observed symptoms. People should avoid exposure to crude oil through avoidance of the affected region, or utilizing hazardous materials suits if involved in cleanup, or wearing hazardous waste operations and emergency response suits if SCUBA diving. Concentrations of alkanes and PAHs in the blood of coastal residents and workers should be monitored through time well after the spill has been controlled.