Rumen microbial community and milk quality in Holstein lactating cows fed olive oil pomace as part in a sustainable feeding strategy.

The use of alternative feed ingredients from the Agro-industry could be an efficient tool to improve the sustainability of dairy cow production. Since the richness in polyphenols, olive oil pomace (OOP), produced during olive oil milling, seems a promising by-product to ameliorate milk's nutritional value. The aim of this study was to test the use of OOP produced by means of a new technology (biphasic with stone deprivation) in dairy cow feeding strategy to evaluate the effect on animal performances, rumen microbiota, biohydrogenation processes and milk quality by a multidisciplinary approach. Forty multiparous Italian-Friesian dairy cows, at middle lactation, were randomly allotted into two homogenous groups and fed respectively a commercial diet (CON) and the experimental diet (OOPD) obtained by adding OOP to CON as partial replacement of maize silage. The two diets were formulated to be isoproteic and isoenergetic. The same diets were tested also in an in vitro trial aimed to evaluate their rumen degradability (% DEG). The dietary supplementation with OOP did not affect DM intake, rumen % DEG and milk production. The milk's nutritional quality was improved by increasing several important functional fatty acids (FAs; i.e., linoleic acid, conjugated linoleic acid, oleic acid, vaccenic acid). This finding was related to a decrease in rumen liquor biohydrogenation rate of unsaturated FAs. The stochiometric relation between volatile FA production in the rumen and methanogenesis suggested that OOP lowers the methane potential production (CON = 0.050 mol/L vs OOPD = 0.024 mol/L, SEM = 0.005, P = 0.0011). Rumen microbiota and fungi community did not be strongly altered by OOP dietary inclusion because few bacteria were affected at the genus level only. Particularly, Acetobacter, Prevotellaceae_UCG-004, Prevotellaceae_UCG-001, Eubacterium coprostanoligenes, Lachnospira, Acetitomaulatum, Lachnospiraceae_NK3A20 group were more abundant with OOPD condition (P < 0.05). Data reported in this study confirm that the use of OOP in dairy cow feeding can be an interesting strategy to improve milk nutritional quality increasing functional FA content without compromising the rumen degradability of the diet or causing strong perturbation of rumen ecosystem and maintaining animal performances.

The genomic and proteomic blueprint of mouse megakaryocytes derived from embryonic stem cells.

BACKGROUND: Platelets are specialized cells, produced by megakaryocytes (MKs) in the bone marrow, which represent the first defense against hemorrhage. There are many diseases where platelet production or function is impaired, with severe consequences for patients. Therefore, new insights into the process of MK differentiation and platelet formation would have a major impact on both basic and clinical research. OBJECTIVES: Embryonic stem (ES) cells represent a good in vitro model to study the differentiation of MKs, with the possibility of being genetically engineered and constituting an unlimited source of MKs. However, lack of knowledge about the molecular identity of ES-derived MKs (ES-MKs) may prevent any further development and application of this model. METHODS: This paper presents the first comprehensive transcriptional and proteome profile analyses of mouse ES-MKs in comparison with MKs derived from mouse fetal liver progenitors (FL-MKs). RESULTS: In ES-MKs we found a down-regulation of cytoskeleton proteins, specific transcription factors and membrane receptors at both transcriptional and protein levels. At the phenotypic level, this molecular blueprint was displayed by ES-MKs' lower polyploidy, lower nuclear/cytoplasm ratio and reduced capacity to form proplatelets and releasing platelets. CONCLUSIONS: Overall our data demonstrate that ES-MKs represent a useful model to clarify many aspects of both MK physiology and pathological conditions where impaired MK functions are related to defective MK development, as in inherited thrombocytopenias and primary myelofibrosis.

Hyperhomocysteinaemia and poor vitamin B status in chronic obstructive pulmonary disease.

BACKGROUND AND AIMS: Patients with chronic obstructive pulmonary disease (COPD) are at increased atherothrombotic risk. Preliminary findings have suggested that COPD patients may have increased plasma total homocysteine (tHcy), a cardiovascular risk factor often caused by a poor B vitamin status, but plasma levels of such vitamins were not measured. The aim of this study was to investigate hyperhomocysteinaemia in COPD and to determine whether it may be secondary to poor plasma concentrations of B vitamins. METHODS AND RESULTS: We performed a case-control, cross-sectional study of 42 patients with COPD and 29 control subjects. Folate, vitamin B12, vitamin B6, tHcy, renal function, C-reactive protein, blood gases and lipids were measured in patients and controls. COPD patients had higher plasma tHcy (median: 13.9mumol/l, interquantile range [IQR]: 12.1-18.5 versus 11.5, IQR: 10.1-14, p=0.002) and lower circulating folate (median: 2.5ng/ml, IQR: 1.2-3.3 versus 2.8, IQR: 2.1-4 of controls, p=0.03) than controls had. Compared to the control group, COPD was associated with higher tHcy concentrations also after adjusting for smoking, heart failure, renal function and C-reactive protein with logistic regression analysis (OR 1.36, 95% CI 1.06-1.72, p=0.01). In the COPD group, low levels of folate (beta=-0.27, p=0.02) and vitamin B12 (beta=-0.24, p=0.04), and hypertriglyceridaemia (beta=0.580, p<0.0001) were independent predictors of the presence of high tHcy concentrations in a multiple linear regression model (adjusted R(2)=0.522). CONCLUSION: COPD patients have a poor B vitamin status and, as a consequence, increased tHcy. These abnormalities may contribute to the COPD-related atherothrombotic risk.

Environmental tobacco smoke and risk of respiratory cancer and chronic obstructive pulmonary disease in former smokers and never smokers in the EPIC prospective study.

OBJECTIVES: To investigate the association between environmental tobacco smoke, plasma cotinine concentration, and respiratory cancer or death. DESIGN: Nested case-control study within the European prospective investigation into cancer and nutrition (EPIC). PARTICIPANTS: 303,020 people from the EPIC cohort (total 500,000) who had never smoked or who had stopped smoking for at least 10 years, 123,479 of whom provided information on exposure to environmental tobacco smoke. Cases were people who developed respiratory cancers or died from respiratory conditions. Controls were matched for sex, age (plus or minus 5 years), smoking status, country of recruitment, and time elapsed since recruitment. MAIN OUTCOME MEASURES: Newly diagnosed cancer of lung, pharynx, and larynx; deaths from chronic obstructive pulmonary disease or emphysema. Plasma cotinine concentration was measured in 1574 people. RESULTS: Over seven years of follow up, 97 people had newly diagnosed lung cancer, 20 had upper respiratory cancers (pharynx, larynx), and 14 died from chronic obstructive pulmonary disease or emphysema. In the whole cohort exposure to environmental tobacco smoke was associated with increased risks (hazard ratio 1.30, 95% confidence interval 0.87 to 1.95, for all respiratory diseases; 1.34, 0.85 to 2.13, for lung cancer alone). Higher results were found in the nested case-control study (odds ratio 1.70, 1.02 to 2.82, for respiratory diseases; 1.76, 0.96 to 3.23, for lung cancer alone). Odds ratios were consistently higher in former smokers than in those who had never smoked; the association was limited to exposure related to work. Cotinine concentration was clearly associated with self reported exposure (3.30, 2.07 to 5.23, for detectable/non-detectable cotinine), but it was not associated with the risk of respiratory diseases or lung cancer. Frequent exposure to environmental tobacco smoke during childhood was associated with lung cancer in adulthood (hazard ratio 3.63, 1.19 to 11.11, for daily exposure for many hours). CONCLUSIONS: This large prospective study, in which the smoking status was supported by cotinine measurements, confirms that environmental tobacco smoke is a risk factor for lung cancer and other respiratory diseases, particularly in ex-smokers.

Chloroplast DNA variation and postglacial recolonization of common ash (Fraxinus excelsior L.) in Europe.

We used chloroplast polymerase chain reaction-restriction-fragment length polymorphism (PCR-RFLP) and chloroplast microsatellites to assess the structure of genetic variation and postglacial history across the entire natural range of the common ash (Fraxinus excelsior L.), a broad-leaved wind-pollinated and wind-dispersed European forest tree. A low level of polymorphism was observed, with only 12 haplotypes at four polymorphic microsatellites in 201 populations, and two PCR-RFLP haplotypes in a subset of 62 populations. The clear geographical pattern displayed by the five most common haplotypes was in agreement with glacial refugia for ash being located in Iberia, Italy, the eastern Alps and the Balkan Peninsula, as had been suggested from fossil pollen data. A low chloroplast DNA mutation rate, a low effective population size in glacial refugia related to ash's life history traits, as well as features of postglacial expansion were put forward to explain the low level of polymorphism. Differentiation among populations was high (GST= 0.89), reflecting poor mixing among recolonizing lineages. Therefore, the responsible factor for the highly homogeneous genetic pattern previously identified at nuclear microsatellites throughout western and central Europe (Heuertz et al. 2004) must have been efficient postglacial pollen flow. Further comparison of variation patterns at both marker systems revealed that nuclear microsatellites identified complex differentiation patterns in south-eastern Europe which remained undetected with chloroplast microsatellites. The results suggest that data from different markers should be combined in order to capture the most important genetic patterns in a species.

Geographic distribution of chloroplast variation in Italian populations of beech (Fagus sylvatica L.).

The distribution of chloroplast DNA (cpDNA) variation in Italian beech ( Fagus sylvatica L.) populations was studied using PCR-RFLP and microsatellite markers. In total, 67 populations were analysed, and 14 haplotypes were identified by combining the two marker types. A remarkable subdivision of cpDNA diversity in Italian beech was found, as indicated by a high level of genetic differentiation ( G(st)=0.855). The highest level of total haplotype diversity ( h(t)=0.822) was estimated for southern Italian populations. The highest number of haplotypes was found in the central-southern region of the peninsula. The nested clade analysis provided evidence for past fragmentation events that may have been occurred during the Quaternary glaciations and had a major role in defining the genetic structure of the central-southern Italian beech populations. Only one haplotype apparently spread towards the north of Italy along the Apennine chain and reached the Italian slope of the western part of the Alps (Maritime Alps, Liguria). All haplotypes found along the Apennines remained trapped in the Italian peninsula. Southern and central Italy represent hotspots of haplotype diversity for Italian beech.

Gene flow among different taxonomic units: evidence from nuclear and cytoplasmic markers in Cedrus plantation forests.

Hybridization and introgression are important natural evolutionary processes that can be successfully investigated using molecular markers and open- and controlled-pollinated progeny. In this study, we collected open-pollinated seeds from Cedrus atlantica, Cedrus libani and C. libani x C. atlantica hybrids from three French-plantation forests. We also used pollen from C. libani and Cedrus brevifolia to pollinate C. atlantica trees. The progeny were analyzed using three different types of molecular markers: RAPDs, AFLPs and cpSSRs. Chloroplast DNA was found to be paternally inherited in Cedrus from the progeny of controlled-crosses. Heteroplasmy, although possible, could not be undoubtedly detected. There was no indication of strong reproductive isolating barriers among the three Mediterranean Cedrus taxa. Gene flow between C. atlantica and C. libani accounted for 67 to 81% of viable open-pollinated seedlings in two plantation forests. We propose that Mediterranean Cedrus taxa should be considered as units of a single collective species comprising two regional groups, North Africa and the Middle East. We recommend the use of cpSSRs for monitoring gene flow between taxa in plantation forests, especially in areas where garden specimens of one species are planted in the vicinity of selected seed-stands and gene-conservation reserves of another species.

Metabolic gene polymorphism frequencies in control populations.

Using the International Project on Genetic Susceptibility to Environmental Carcinogens (GSEC) database containing information on over 15,000 control (noncancer) subjects, the allele and genotype frequencies for many of the more commonly studied metabolic genes (CYP1A1, CYP2E1, CYP2D6, GSTM1, GSTT1, NAT2, GSTP, and EPHX) in the human population were determined. Major and significant differences in these frequencies were observed between Caucasians (n = 12,525), Asians (n = 2,136), and Africans and African Americans (n = 996), and some, but much less, heterogeneity was observed within Caucasian populations from different countries. No differences in allele frequencies were seen by age, sex, or type of controls (hospital patients versus population controls). No examples of linkage disequilibrium between the different loci were detected based on comparison of observed and expected frequencies for combinations of specific alleles.

Genetic determinants of alcohol addiction and metabolism: a survey in Italy.

BACKGROUND: Although multiple genes are involved in alcoholism and can contribute differently to the risk of dependence and liver damage, no studies have investigated susceptibility to addiction in combination with susceptibility to liver damage due to differences in ethanol metabolism. METHODS: We evaluated the role of three polymorphic genes related to alcohol metabolism (CYP2E1) and, possibly, dependence (DRD2 and SLC6A4 promoter) in a series of 60 alcoholics admitted to a specialized referral center in Florence, Italy. Eighteen had a diagnosis of liver cirrhosis. A control series of 64 blood donors were identified at the same hospital. Genotyping was done by polymerase chain reaction-restriction fragment length polymorphism methods. RESULTS: No difference was found in the frequency of the CYP2E1 Rsal c2 allele (2.5% among alcoholics and 4.7% among controls) and the DraI C allele (6.7% and 10.1%). Similarly, no difference was found in the frequency of the DRD2 A1 allele (15.8% and 13.3%) and the B1 allele (10.8% and 8.6%). The proportion of controls with a combined B1 genotype (B1/B1 or B1/B2) was significantly associated with smoking (p = 0.03). The distribution of the S and L allele of the SLC6A4 gene was similar in the two groups, with 15% and 14%, respectively, homozygous S/S carriers. A significant association, however, emerged in the group of alcoholics, with a five times higher risk for S/S carriers of developing cirrhosis (p < 0.05). This association with liver persisted even after exclusion of the subgrouped of 10 hepatitis C virus positive alcoholics. CONCLUSIONS: Overall, our results provided no evidence of an increased susceptibility to develop alcoholism that was associated with the three genotypes investigated, either alone or in combination. An increased risk of developing liver cirrhosis for S/S homozygous carriers among alcohol-dependent patients was observed for the first time.

Benzo(a)pyrene diolepoxide adducts to albumin in workers exposed to polycyclic aromatic hydrocarbons: association with specific CYP1A1, GSTM1, GSTP1 and EHPX genotypes.

We investigated whether the presence of (+)-anti-benzo(a)pyrene diolepoxide adducts to serum albumin (BPDE-SA) among workers exposed to benzo(a)pyrene (BaP) and unexposed reference controls was influenced by genetic polymorphisms of cytochrome P4501A1 (CYP1A1), microsomal epoxide hydrolase (EHPX), glutathione S-transferases M1 (GSTM1) and P1 (GSTP1), all involved in BaP metabolism. Exposed workers had significantly higher levels of adducts (0.124 ± 0.02 fmol BPTmg(-1) SA, mean ± SE) and a higher proportion of detectable adducts (40.3%) than controls (0.051 ± 0.01 fmol BPT mg(-1) SA; 16.1%) (p = 0:014 and p = 0:012). Smoking increased adduct levels only in occupationally exposed workers with the GSTM1 deletion (GSTM1 null) (p = 0:034). Smokers from the exposed group had higher adduct levels when they were CYP1A1 *1/*1 wild-type rather than heterozygous and homozygous for the variant alleles (CYP1A1 *1/*2 plus *2/*2) (p = 0:01). The dependence of BPDE-SA adduct levels and frequency on the CYP1A1 *1/*1 genotype was most pronounced in GSTM1-deficient smokers. Exposed workers with GSTM1 null/GSTP1 variant alleles had fewer detectable adducts than those with the GSTM1 null/GSTP1*A wild-type allele, supporting for the first time the recent in vitro finding that GSTP1 variants may be more effective in the detoxification of BPDE than the wild-type allele. Logistic regression analysis indicated that occupational exposure, wild-type CYP1A1*1/*1 allele and the combination of GSTM1 null genotype+EHPX genotypes associated with predicted low enzyme activity were significant predictors of BPDE-SA adducts. Though our findings should be viewed with caution because of the relatively limited size of the population analysed, the interaction between these polymorphic enzymes and BPDE-SA adducts seems to be specific for high exposure and might have an impact on the quantitative risk estimates for exposure to polycyclic aromatic hydrocarbons.

Revision of species delineation in the genus Ectothiorhodospira.

When the type strains and other strains of the six currently defined species of the genus Ectothiorhodospira were examined by DNA-DNA reassociation and RFLP of 16S/23S rDNA (ribotype), only four genospecies could be found. The possibility of defining taxonomically meaningful species corresponding to these four genospecies was investigated by combining DNA relatedness and ribotype data with other genotypic and phenotypic characters already described in the literature, an approach known as polyphasic taxonomy. Following this comparison, the type strain and another strain of Ectothiorhodospira vacuolata were found to be very similar to the type strain of Ectothiorhodospira shaposhnikovii and have been transferred to this latter species. Also, the type strain of Ectothiorhodospira marismortui and another previously unidentified strain were found to be very similar to the type strain of Ectothiorhodospira mobilis and have been transferred to this latter species. Due to the limited degree of reciprocal DNA relatedness, strains belonging either to Ectothiorhodospira marina or to Ectothiorhodospira haloalkaliphila are still considered as belonging to separate species, even though they show a remarkable phenotypic similarity. This revision has led to the delineation of only four species in the genus Ectothiorhodospira, namely E. mobilis, E. shaposhnikovii, E. marina and E. haloalkaliphila. E. vacuolata is recognized as a junior synonym of E. shaposhnikovii and E. marismortui as a junior synonym of E. mobilis.

Benzo(a)pyrene diolepoxide-haemoglobin and albumin adducts at low levels of benzo(a)pyrene exposure.

A biomonitoring study was conducted to simultaneously measure individual benzo(a)pyrene (BaP) exposure in 50 office employees, not occupationally exposed to polycyclic aromatic hydrocarbons (PAH), using personal samplers and the formation of (+) r-7, t-8-dihyroxy-t-9,t-10-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene (BPDE) adducts to haemoglobin (BPDE-Hb) and serum albumin (BPDE-SA). The population enrolled was exposed to an average of 0.58 ± 0.46 ng BaP m(-3) (mean ± SD). The concentration of BaP collected from smokers' samples was double that from non-smokers (P = 0.007). BPDE adducts to Hb and SA were quantified as BaP tetrols released from hydrolysis of macromolecules and measured by high-resolution gas chromatography-negative ion chemical ionization-mass spectrometry. BPDE-Hb adducts were detected in 16% of the population and BPDE-SA adducts in 28%. Smoking did not affect adduct formation. When BaP personal monitoring data were used as the criterion of exposure, no correlation was found with the presence and the levels of BPDE-Hb and BPDE-SA adducts. Undetected sources of PAH, such as the diet, might markedly alter the exposure profile depicted by individual air sampling and affect the frequency and levels of protein biomarkers. This is the first comparative analysis of BPDE-Hb and BPDE-SA adducts, providing reference values for these biomarkers in a general urban population. However it is difficult to establish which biomarkers would be the more relevant in assessing low BaP exposure, due to undetectable factors such as dietary PAHs, that might have influenced the results to some degree.

Seasonal effect on airborne pyrene, urinary 1-hydroxypyrene, and benzo(a)pyrene diol epoxide-hemoglobin adducts in the general population.

Exposure to airborne polycyclic aromatic hydrocarbons (PAHs) in 65 employees (40 sampled both in summer and winter, 15 sampled in summer only, and 10 sampled in winter only) with no occupational exposure to PAHs was assessed by measuring: personal exposure to pyrene, urinary excretion of 1-hydroxypyrene (1-OHP), and benzo(a)pyrene diol epoxide adducts to hemoglobin (BPDE-Hb). Overall, office employees were exposed to significantly higher levels of pyrene in winter (4.54 +/- 2.35 ng/m3, mean +/- SD) than in summer (1.67 +/- 1.92 ng/m3, mean +/- SD; P < 0.001), but no such seasonal variability was observed in 1-OHP excretion. Tobacco smoking was the major determinant of 1-OHP excretion. BPDE-Hb adducts were measured by gas chromatography-mass spectrometry as benzo(a)pyrene tetrols (BPT) released from adducted hemoglobin. In the 65 employees analyzed, mean BPT levels +/- SD were higher in winter (0.14 +/- 0.38 fmol/mg Hb) than summer (0.031 +/- 0.022 fmol/mg Hb). This difference was not statistically significant, probably because of the small proportion of subjects with detectable adducts (11% in summer and 16% in winter). BPDE-Hb adducts were not significantly associated with sex, age, diet, smoking habits, or with pyrene levels and 1-OHP excretion. This is the first report providing reference BPDE-Hb adduct values for the general population not occupationally exposed to environmental PAHs and shows a tendency to seasonal variability, with higher BPT levels in winter when environmental PAHs are also high.

Carcinogen-DNA adducts as tools in risk assessment.

Genotoxic chemicals are known to react with DNA either directly or after metabolic activation to form adducts, a step thought to be relevant with respect to chemical carcinogenesis. Evaluation of cancer risk due to exposure to chemicals requires information about the internal dose which depends on individual variation in rates of metabolic activation and detoxification. The presence and the amount of specific DNA adducts provide a good indication of chemical exposure and genetic damage resulting from exposure to carcinogens and account for some of the factors affecting individual susceptibility to cancer. Analysis of DNA adducts requires that the sensitivity of the methods be sufficiently high to allow the detection of about 1 adduct/109 normal nucleotides. Most suitable methods are based on 32P-postlabelling, immunoassays or physico-chemical techniques such as HPLC coupled to synchronous fluorescence spectroscopy or gas chromatography-mass spectrometry. These methods have been used to assess human exposure to a variety of chemical carcinogens including polycyclic aromatic hydrocarbons, aromatic amines, heterocyclic aromatic amines or aflatoxins. In some instances, the use of DNA-adducts has given accurate estimates of risk.

Impact of inherited polymorphisms in glutathione S-transferase M1, microsomal epoxide hydrolase, cytochrome P450 enzymes on DNA, and blood protein adducts of benzo(a)pyrene-diolepoxide.

The benzo(a)pyrene (BaP) metabolite benzo(a)pyrenediolepoxide (BPDE) is strongly implicated as a causative agent of lung cancer. To assess the risk of exposure to BaP, we made a combined analysis of levels of BPDE adducts to hemoglobin (Hb), serum albumin (SA), and lymphocyte DNA in 44 patients with incident lung cancer, as a prototype of a population mainly exposed to tobacco-derived BaP. We also investigated whether genetic polymorphisms of cytochrome P450IA1 (CYPIA1), microsomal epoxide hydrolase (mEH), and glutathione S-transferase M1 (GSTM1), which are involved in BaP metabolism, can be determinants of adduct formation. BPDE-Hb, BPDE-SA, and BPDE-DNA adducts were quantified as BaP tetrols released from hydrolysis of macromolecules and measured by high-resolution gas chromatography-negative ion chemical ionization-mass spectrometry to achieve high specificity and sensitivity. Individuals with detectable Hb adducts were positive for SA adducts but not vice versa, suggesting that BPDE-Hb adducts are less informative indicators of BaP exposure. Using PCR methods on DNA, we characterized GSTM1 deletion, CYPIA1 MspI and exon 7 valine variants, and mEH polymorphisms at amino acid positions 113 (EH3) and 139 (EH4). Levels of BPDE adducts were no different among CYPIA1, mEH, and GSTM1 genotypes. However, individuals with measurable BPDE-SA adducts were CYPIA1 variant carriers more frequently (P = 0.03). There was a slightly higher percentage of DNA detectable adducts in subjects with CYPIA1 exon 7 valine polymorphism. When subjects were classified by both polymorphisms on the mEH gene, those with two slow alleles (EH3 homozygous mutated) and no fast alleles (EH4 homozygous wild type) had a lower frequency of BPDE-SA adducts and no DNA adducts (P = 0.06). These results are based on a small number of observations thus far, but this exploratory study suggests that CYPIA1 and mEH variants might have an impact on BPDE exposure markers such as BPDE-SA adducts. Chemical specificity in adduct measurements is important to identify the biomarkers that reflect BaP exposure more accurately.

3,4 Dichloroaniline-haemoglobin adducts in humans: preliminary data on agricultural workers exposed to propanil.

Propanil is one of the major herbicides used on rice-paddies and is thought to produce adverse health effects through the action of its metabolite 3,4-dichloroaniline (3,4-DCA). T he feasibility of monitoring human exposure to propanil on the basis of 3,4-DCA adducts to haemoglobin (Hb) was investigated. We developed a method based on gas chromatography negative ion chemical ionization-mass spectrometry (NICI-GC-MS) to quantify 3,4-DCA released from human Hb after alkaline hydrolysis of the protein. 3,4-DCA-Hb adducts were identified in agricultural workers exposed to propanil and were detectable even 4 months after the last herbicide application. Urine samples collected at the same time had no measurable level of 3,4-DCA. 3,4-DCA-Hb adducts might be useful for monitoring human exposure to 3,4-DCA from agricultural sources.

Hemoglobin adducts of benzo[a]pyrene diolepoxide in newspaper vendors: association with traffic exhaust.

Benzo[a]pyrene diol epoxide adducts with hemoglobin (Hb) were measured to detect human exposure to environmental benzo[a]pyrene from traffic exhaust. Benzo[a]pyrene tetrahydrotetrols (BPTs) released from Hb after acid hydrolysis were quantitated by gas chromatography-mass spectrometry after immunoaffinity chromatography. Fifty three newspaper vendors were enrolled. The median adduct concentration was 0.3 fmol BPTs/mg Hb in high density traffic-exposed vendors and < or = 0.1 fmol BPTs/mg Hb in those exposed to low density traffic; the difference was not significant (P = 0.09). Among non-smokers, adducts were detectable in 60% of high exposure subjects (median 0.3 fmol BPTs/mg Hb) and in 28% of those with low exposure (median < or = 0.1 fmol/mg Hb). This difference was significant (P = 0.02). In low exposure smokers the median of adducts was 0.26 fmol BPTs/mg Hb, while in low exposure non-smokers it was < or = 0.1 fmol BPTs/mg Hb (P = 0.08, not significant). Adduct concentration was no different for low and high density traffic-exposed smokers (P = 0.82). The data indicate a significant difference in adduct concentration related to traffic exhaust exposure among non-smokers.