Quercetin ameliorates polychlorinated biphenyls-induced testicular DNA damage in rats.

Polychlorinated biphenyls (PCBs) are a group of environmental contaminants widely reported to cause gonadal toxicity in both humans and animals. This study investigated the amelioratory role of quercetin in PCBs-induced DNA damage in male Wistar rats. Polychlorinated biphenyls were administered intraperitoneally at a dose of 2 mg kg(-1) alone or in combination with quercetin (orally) at 50 mg kg(-1) for 25 days. Quercetin modulation of PCBs-induced gonadal toxicity was evaluated using selected oxidative stress indices, comet assay, measurement of DNA concentration and histology of the testes. Administration of PCBs alone caused a significant (P < 0.05) depletion in the total thiol level in testes of treated rats. Conversely, the levels of reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) production were markedly elevated in testes of PCBs-treated rats compared with control. Further, PCBs exposure produced statistically significant increases in DNA tail migration, degraded double-stranded DNA (dsDNA) concentration and histological alterations of testes of the treated rats compared to control. Quercetin cotreatment significantly improved the testicular antioxidant status, decreased DNA fragmentation and restored the testicular histology, thus demonstrating the protective effect of quercetin in PCBs-treated rats.

Assessment of polychlorinated biphenyls (PCBs) in cheese from Rio Grande do Sul, Brazil.

Polychlorinated biphenyls (PCBs) are among the most toxic environmental pollutants. Food, especially animal based, has been described as the major source for human exposure to PCBs. We investigated PCB levels (congeners 10, 28, 52, 153, 138, and 180) in cheese from 14 cities of Rio Grande do Sul, Brazil. The fat was extracted using sodium sulfate and petroleum ether, and PCBs purification was conducted using florisil and hexane. The identification and quantification were made in a gas chromatograph with microelectron capture detector (GC-microECD). PCB congeners were found (lower bound data as ngg(-1) fat) in the following rank: 52 (15.75)>180 (4.91)>28 (3.43)>153 (3.00)>10 (2.38)>138 (1.37). Summation operatorPCB contamination ranged from 0 to 78.32 ngg(-1) fat. Differences in PCB levels between industrialized (33.32 ngg(-1) fat) and homemade (26.58 ngg(-1) fat) cheese and between two different regions (36.19 vs. 26.95 ngg(-1) fat) were not statistically significant. For university students, the estimated daily intake (EDI) of PCBs from cheese ranged from 0 to 3.13 pgkg(-1) b.w. EDI was significantly higher for industrialized than homemade cheese, and for cheese from Mountain/Porto Alegre region than from Santa Maria/South/Western region. No sample exceeded maximum level of PCBs allowed in dairy products in the European Community.

Degradation of polychlorinated biphenyls (PCBs) by Staphylococcus xylosus in liquid media and meat mixture.

We investigated the growth of the meat starter Staphylococcus xylosus (10(4) cells mL(-1)) in liquid media containing 0.01 ppm of each polychlorinated biphenyls (PCBs 10, 28, 52, 138, 153, and 180) and its ability to degrade PCBs during 168 h of incubation in liquid media (10(4) cells mL(-1), 0.01 ppm of each PCB congener) and cured meat mixture (0.1% of meat starter, 1 microg g(-1) fat of each PCB congener). PCBs did not affect the growth of the starter microorganism in nutritive (brain heart infusion, BHI) or mineral salts medium (MSM) when compared to control (no PCB). S. xylosus degraded some of the PCB congeners tested. PCBs 138 and 153 were degraded both in BHI (78% and 68%, respectively; p<0.05) and in MSM (71% and 66%, respectively; p<0.05), with maximum degradation being observed within 24 h. Highly significant negative exponential relationships was observed between incubation time and concentrations of PCB 28 and 180 in BHI, as well as for PCBs 52 and 180 in MSM. In the cured meat mixture highly significant negative exponential relationship was observed between incubation time and the concentration of PCB 10. These results indicate that although S. xylosus reduced residues of various PCB congeners in liquid media, it was less effective in cured meat.

Levels of polychlorinated biphenyls (PCBs) in meat and meat products from the state of Rio Grande do Sul, Brazil.

The levels of six polychlorinated biphenyl congeners (PCBs) were evaluated in 55 samples of meat (bovine and pork) and meat products (sausage, hot dog sausage, bologna sausage, canned export meat and salami) from 11 cities of the state of Rio Grande do Sul, Brazil, between July and August 2002. PCB congeners were found (in fat basis) in the following rank 52 (5.18 ng/g) > 180 (1.69 ng/g) > 10 (1.35 ng/g) > 28 (1.19 ng/g) >153 (0.47 ng/g) >138 (0.43 ng/g), with a summation SigmaPCB amounting to 10.30 ng/g. Meat products had higher PCB levels than meat. PCB levels in samples followed the rank: mixed meat products > pork meat > bovine meat. These results indicate the presence of PCBs in food samples from Rio Grande do Sul, Brazil, but the levels found were well below the maximum level established for animal food products in Brazil (3000 ng/g fat). Only one sample exceeded the maximum level established by the European Community (200 ng/g fat). This is the first paper describing background concentrations of PCBs in meat and meat products from Brazil.

Influence of alimentary habits, age and occupation on polychlorinated biphenyl levels in adipose tissue.

The levels of polychlorinated biphenyls (PCBs) in adipose tissue samples from the mammary glands of 123 women living in Cordoba (Spain) were evaluated. The influence of alimentary habits, age and previous and present occupation on the tissue levels of PCBs were also investigated. The compound found at the highest concentration was PCB 180 (0.134 microg/g), followed by the congeners 153 (0.121 microg/g), 138 (0.102 microg/g), 187 (0.047 microg/g), 170 (0.046 microg/g), 28 (0.039 microg/g), 118 (0.023 microg/g), 183 (0.020 microg/g), 52 (0.011 microg/g), 188 (0.011 microg/g), and 101 (0.002 microg/g). A positive correlation was found between donor age and tissue levels of PCBs 28, 118, 138, 153, 170, 180, 183 and 187. Conversely, age had no influence on tissue levels of PCBs 52 and 101. The majority of donors (40.65%) reported fruits as the most consumed food, followed by mixed food (34.15%), legumes and root vegetables (6.5%), stewed meat and vegetables (6.5%), leafy vegetables (4.88%), milk (3.25%), fish (2.44%) and meat (1.63%). "Farmer" (38%) and "housewife" (38%) were the most frequent previous occupations, followed by "other activities" (24%), while "housewife" was the most frequent present occupation (67%), followed by "other activities" (24%) and "farmer" (9%). No significant correlation was observed between tissue levels of PCBs and alimentary habits or previous or present occupation of donors.

Breast cancer risk factors: PCB congeners.

The chronic effects of polychlorinated biphenyls (PCBs) are a public health concern, and a potential relationship with breast cancer has been postulated. The purpose of this study was to examine the possible relationship between PCBs and breast cancer. All women (134) treated by excision biopsy because of breast lump at Reina Sofia University Hospital, Cordoba, Spain over a period of 10 months were included in our study. They were all administered a questionnaire by interview, calculation of body mass index, histopathological examination of excised mass and chemical estimation of PCB congener levels in breast fat. The collected samples were from 65 (48.5%) women with benign lesions and 69 (51.5%) with malignant lesions. The variables associated with malignant lesions on univariate analysis were age, lactation period, overweight, PCB n-28 and PCB n-52. On the multivariate analysis PCB n-28 was found to be the most important risk factor (OR 9.6, 95% CI 3.8-24.4). Other risk factors were identified as age, drinking alcohol, low parity and overweight. If these findings can be confirmed in a large study population, however, they may have important implications for breast cancer risk.