Blood Polycyclic Aromatic Hydrocarbons Research Articles

Occurrence and probabilistic risk assessment of polycyclic aromatic hydrocarbons in blood and urine of auto-mechanics in Akure Metro, Nigeria

This study provides baseline data on the concentration of polycyclic aromatic hydrocarbons (PAHs) in blood and urine samples of auto-mechanics, using Nigeria as a case study. Eighteen auto-mechanics participated in the study excluding two controls. The concentrations for the ΣPAHs across all participants (excluding control) ranged from 1.67 to 3.30 (2.17 ± 0.58) in blood with a significantly higher (P < 0.05) range of 7.61 to 10.76 (8.69 ± 1.00) in urine. The high molecular weight PAHs (4-6 rings) dominated the PAH profile in both blood (≥ 92%) and urine (≥ 87%) across all locations. Dibenz(a)anthracene was the most distributed PAH, while acenaphthene and indeno(1,2,3-cd)pyrene were the least distributed. The dermal route constituted approximately 99% of the total chronic exposure, followed by ingestion, and the least via inhalation. The hazard index (HI) was below the safe thresholds (HI = 1), suggesting non-carcinogenic PAH effects. However, all the participants including control samples had carcinogenic risk (CR) values above the acceptable level of 10-6 in both blood and urine samples. The carcinogenic and mutagenic potencies were higher in urine than in blood. The results suggest less acute toxicity and more potential chronic effects. The computed elimination ratio (> 1) suggests low excretion in urine and a potentially harmful trend. Molecular diagnostic ratios and principal component analysis suggest mixed PAH sources. The study revealed biomonitoring solely dependent on blood analysis may greatly underestimate health risks due to PAH exposure. To the best of our knowledge, this study is the first to provide levels of PAHs in the blood and urine of Nigerian mechanics. Findings herein will support policymakers at all levels in re-focusing attention to the less prioritized professions that pre-disposes people to PAHs and other emerging pollutants in society.

Biomonitoring of concentrations of polycyclic aromatic hydrocarbons in blood and urine of children at playgrounds within Owerri, Imo State, Nigeria.

Polycyclic aromatic hydrocarbons (PAHs) exposure is among the leading air pollutants associated with diverse adverse health effects due to their persistent, bio-accumulative and toxic characteristics. Children are most affected by these pollutants, yet studies directly related children to these pollutants are scarce in Nigeria. In this study, blood and urine from 36 children between the ages 4-14 years were collected as per sterile procedures by a licensed phlebotomist from the antecubital fossa into BD vacutainer tubes® while a mid-stream urine sample into acid-washed 120 mL BD vacutainer urine cups and stored in refrigerator at –4˚C for 6 hours, then each 5 mL was extracted with 10 mL of pentane and analyzed for 15 PAHs using GC-MS. Results revealed that PAHs concentrations (53.48 to 70.8 μg/dL) in blood was lower than in urine (94.98 to 115.04 μg/dL). Mean values had no significant (p>0.5) differences between schools, possibly due to the fact that all schools were experiencing similar anthropogenic disturbances. At 5% level of significance, positive and strong correlationships (r=0.83, r=0.73) were observed for fluorene-fluoranthene (FLa) and benzo (a) anthracene-FLa respectively in blood samples. Two and three rings PAHs had generally low concentrations in both blood and urine. Despite being the most distributed compound, the concentration of dibenzo (a,h) anthracene was highest for urine than in blood. Urine PAHs showed higher concentration of carcinogenic PAHs than blood. Elimination ratios (ER) such as for acenaphthene (0.06) and anthracene (Ant; 0.11) were considered low while values such as for FLa (1.36) and indeno [1, 2, 3-cd] pyrene (1.55) were considered high ER. Trends in elimination ratios showed close similarity. In conclusion there was elevated PAHs in blood and urine of children with consequent high carcinogenic and then non-carcinogenic risks. This research is significant in setting the stage for more detailed work at same time alerting policy makers on the need for urgent mitigation steps that will reduce children exposure to this class of dangerous pollutants.

Blood levels of Polycyclic Aromatic Hydrocarbons in Women with Benign and Malignant Breast Lesions: A case-control study

Objective: As part of our program to investigate the possible role of environmental pollutants in the incidence of breast cancer in India, we conducted for the first time a hospital based case-control study where blood polycyclic aromatic hydrocarbons (PAHs) levels were determined in women suffering from benign and malignant breast lesions, and compared with those of disease free controls drawn from similar socioeconomic environment residing in and around New Delhi, India. Material &amp; Methods: Anthracene, phenanthrene, fluoranthene, naphthalene, pyrene, benzo (a) pyrene, benzo (k) fluoranthene and dibenzo (a,h) anthracene were determined by HPLC-FD. Results: Level of total PAHs in control, benign and malignant groups (30 numbers in each) were 142.05 ± 50.84, 185.99 ± 61.97 and 200.74 ± 55.05 μg / L respectively. Mean levels of naphthalene, phenanthrene, pyrene and benzo (k) fluoranthene were higher in both malignant and benign groups than in control but the difference was not statistically significant. Of the total PAHs, 3–ringed compounds were found much higher (89%) in controls than in benign (52%) and malignant groups (54%). However, the percentage sum of 2, 4 and 5-ringed PAHs were much higher in malignant (46%) and benign (48%) groups when compared with those of controls (11%). Conclusion: Results of the present study indicate that higher levels of PAHs (especially non-carcinogenic), though statistically non-significant, were present in cases with benign and malignant breast lesions than in those of controls. Key Words: Polycyclic Aromatic Hydrocarbons; Breast cancer; Benign lesions; HPLC-FD DOI: 10.3126/ajms.v1i2.2924Asian Journal of Medical Sciences 1 (2010) 80-86