Polycylic aromatic hydrocarbons

The text on this page is taken from an equivalent page of the IEHIAS-project.

The most commonly used biomarkers of PAH-exposure are metabolites of PAHs, particularly 1-Hydroxypyrene (1-OH) and PAH-DNA or –protein adducts.

as a biomarker

Sample collection and storage

Matrix:

• DNA- and protein adducts are determined in blood (white blood cells or lymphocytes) or placenta.
• 1-OH is determined in urine

Kinetics:

• Total intake of carcinogenic PAHs is estimated at 3 µg/day for non-smokers.
• Main sources of PAHs for non-smokers are occupation, food and air pollution.
• Tobacco smoke adds around 2-5 µg/day for a 1 pack/day smoker.
• The half-life of 1-OH is about 18-20 hours,
• The half-life of DNA-adducts is in the order of months
• Half-life is 20-120 days for protein adducts, depending on the type of protein.

Sampling conditions:

Urine or blood samples can be gathered and stored using standard protocols

Sample measurement

Analytical aspects: 1-OH is mainly analysed using either HPLC and fluorescence detection, or GC/MS

Performance characteristics:

• Detection limits are around 0,05 µg/l for HPLC, and 0,1 µg/l for GC/MS.
• DNA-adducts are measured using ELISA and ³²P-Postlabelling techniques.
• Protein adducts are measured in blood proteins using GC/MS, HPLC or ELISA.

Validation:

Standardization of ³²P-postlabelling was organized by IARC

Confounding factors:

Higher intake of vitamin C may affect the level of DNA adducts in the placenta, and also ethnicity may have an influence of DNA adduct levels

Data interpretation

Concentrations reported in literature:

Dose-response/effect relationships:

• Significant correlations are observed between individual personal exposure and DNA-adducts.
• PAH exposure also correlates with oxidative stress, comet assay and other genotoxic endpoints.

Time trend, geographical variation, susceptibel groups:

• PAH levels are frequently higher in winter than summer due to residential heating.
• Studies have additionally suggested an increased susceptibility of the developing foetus