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- Rignell-Hydbom, Anna, et al.
(författare)
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Exposure to cadmium and persistent organochlorine pollutants and its association with bone mineral density and markers of bone metabolism on postmenopausal women
- 2009
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Ingår i: Environmental Research. - : Elsevier BV. - 0013-9351 .- 1096-0953. ; 109:8, s. 991-996
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Tidskriftsartikel (refereegranskat)abstract
- Environmental contaminants such as cadmium and persistent organochlorine pollutants have been proposed as risk factors of osteoporosis, and women may be at an increased risk. To assess associations between exposure to cadmium and two different POPs (2,2',4,4',5,5'-hexachlorobiphenyl CB-153, 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene p,p'-DDE), on one hand, and bone effects, on the other, in a population-based study among postmenopausal (60-70 years) Swedish women with biobanked blood samples. The study included 908 women and was designed to have a large contrast of bone mineral densities, measured with a single photon absorptiometry technique in the non-dominant forearm. Biochemical markers related to bone metabolism were analyzed in serum. Exposure assessment was based on cadmium concentrations in erythrocytes and serum concentrations of CB-153 and p,p'-DDE. Cadmium was negatively associated with bone mineral density and parathyroid hormone, positively with the marker of bone resorption. However, this association disappeared after adjustment for smoking. The major DDT metabolite (p.p'-DDE) was positively associated with bone mineral density, an association which remained after adjustment for confounders, but the effect was weak. There was no evidence that the estrogenic congener (CB-153) was associated with any of the bone markers. In conclusion, no convincing associations were observed between cadmium and POPs, on one hand, and bone metabolism markers and BMD, on the other. (C) 2009 Elsevier Inc. All rights reserved.
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| 2. |
- Balatsouka, Dimitra, et al.
(författare)
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The impact of nicotine on bone healing and osseointegration.
- 2005
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Ingår i: Clinical oral implants research. - : Wiley. - 0905-7161 .- 1600-0501. ; 16:3, s. 268-76
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To examine the short-term effect of nicotine on bone healing and osseointegration. MATERIAL AND METHODS: Sixteen female rabbits were divided into two groups. The test group was exposed to nicotine tartrate for 8 weeks and the control group was exposed to placebo. Nicotine or placebo was administered via a miniosmotic pump and plasma cotinine levels were measured weekly. The pump delivered 15 mg of nicotine/day for the animals in the test group. All rabbits had three tibial bone preparations. In the proximal and distal bone bed, implants were placed after 4 weeks (right tibia) and after 6 weeks (left tibia). Thus, 2- and 4-week healing groups were created. Removal torque test (RMT) was performed at the distal implants. Ground sections were made from the proximal and the central bone beds. The fraction of mineralized bone in contact to the implant (BIC) and the bone density within the implant threads (BD-i) were determined for the bone-implant specimens. For the central bone beds without implants the bone density (BD-c) in the bone defects was determined. RESULTS: No significant difference in RMT values was found between the test and the control group. Histomorphometric measurements of the BIC and the peri-implant BD-i showed no significant differences between the test and the control group after 2 or 4 weeks. Significant differences were, however, found between the 2- and 4-week samples. In the central bone beds, there was no significant difference in BD-c between the test and the control group. CONCLUSION: Nicotine exposure in a short period of time did not have a significant impact on bone healing or implant osseointegration in rabbits.
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| 3. |
- Vermeulen, R, et al.
(författare)
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Biological monitoring of carbon disulphide and phthalate exposure in the contemporary rubber industry
- 2005
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Ingår i: International Archives of Occupational and Environmental Health. - : Springer Science and Business Media LLC. - 1432-1246 .- 0340-0131. ; 78:8, s. 663-669
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: We studied the range in urinary levels of 2-thiothiazolidine-4-carboxyl acid (TTCA), a metabolite of CS, and phthalic acid (PA), a common metabolite of phthalates, across factories and departments in the contemporary rubber manufacturing industry. Methods: Spot urine samples from 101 rubber workers employed in nine different factories were collected on Sunday and during the workweek on Tuesday, Wednesday and Thursday at similar to 4 pm. In total, 386 urine samples were successfully analyzed. Results: Levels of both biomarkers increased significantly by a factor 2 (paired t-test P-value < 0.05) during the working week as compared to the Sunday biomarker levels with absolute increases of approximately 70 mu g/l and 5 mu mol/mol creatinine for PA and TTCA, respectively. Levels in both biomarkers did not differ markedly between working days. Increases seemed to be restricted to specific factories and/or departments (e.g. molding and curing). Conclusions: The results of this study demonstrate that rubber workers in the contemporary rubber industry are exposed to phthalates and low levels Of CS2 (similar to 0.05 ppm) as measured by PA and TTCA, respectively. Exposures to both compounds are largely driven by specific circumstances in Factories. Therefore, when estimating exposures to phthalates and CS2 detailed information should be collected on the type and amount of phthalate containing ester plasticizers, dithlocarbamates and thiurams used. Preferably, personal exposure data should be collected. In this case, biological monitoring seems a reasonable approach. However, in the case of PA attention should be given to individual background levels as this could lead to a substantial overestimation of the Occupational contribution to total phthalate exposure.
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