Elevated levels of whole blood nickel in a group of Sri Lankan women with endometriosis: a case control study

<p>Abstract</p> <p>Background</p> <p>Endometriosis is characterized by the persistence of endometrial tissue in ectopic sites outside the uterine cavity. Presence of nickel, cadmium and lead in ectopic endometrial tissue has been reported previously. While any association between blood levels of nickel and endometriosis is yet to be described in literature, conflicting reports are available with regards to cadmium and lead levels in blood and urine.</p> <p>Findings</p> <p>In fifty patients with endometriosis and fifty age-matched controls confirmed by laparoscopy or laparotomy, whole blood samples were collected and digested using supra pure 65% HNO₃. Whole blood levels of nickel and lead were measured using Total Reflection X-ray Fluorescence (TXRF) while cadmium levels were evaluated using graphite furnace atomic absorption spectroscopy (GFASS). Women with endometriosis had significantly higher (<it>P</it>=0^.016) geometric mean (95% CI) whole blood nickel levels [2.6(1.9-3.3) μg/L] as compared to women without endometriosis [0.8 (0.7-0.9) μg/L]. Whole blood levels of cadmium and lead were similar between the two groups.</p> <p>Conclusions</p> <p>Although women with endometriosis in this study population had higher levels of nickel in whole blood compared to controls, whether nickel could be considered as an aetiological factor in endometriosis remains inconclusive in view of the smaller sample that was evaluated.</p

Dioxin-induced changes in epididymal sperm count and spermatogenesis Mudanças induzidas por dioxina na contagem epididimal de esperma e espermatogênese

A single in utero exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on gestation day 15 decreased epididymal sperm count in adult rats and thus was used to establish a tolerable daily intake for TCDD. However, several laboratories have been unable to replicate these findings. Moreover, conflicting reports of TCDD effects on daily sperm production suggest that spermatogenesis may not be as sensitive to the adverse effects of TCDD as previously thought. We performed a PubMed search using relevant search terms linking dioxin exposure with adverse effects on reproduction and spermatogenesis. Developmental exposure to TCDD is consistently linked with decreased cauda epididymal sperm counts in animal studies, although at higher dose levels than those used in some earlier studies. However, the evidence linking in utero TCDD exposure and spermatogenesis is not convincing. Animal studies provide clear evidence of an adverse effect of in utero TCDD exposure on epididymal sperm count but do not support the conclusion that spermatogenesis is adversely affected. The mechanisms underlying decreased epididymal sperm count are unknown; however, we postulate that epididymal function is the key target for the adverse effects of TCDD.<br>Uma única exposição in utero a 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) no 15º dia de gestação diminuiu a contagem de esperma epididimal em ratos adultos e por isso foi utilizada para estabelecer uma dosagem diária tolerável para TCDD. No entanto, diversos laboratórios não conseguiram reproduzir esses resultados. Além disso, relatórios conflitantes dos efeitos de TCDD na produção diária de esperma sugere que espermatogênese pode não ser tão sensível aos efeitos adversos do TCDD como antes se pensava. Foi feita uma pesquisa no PubMed usando termos de pesquisa relevantes, relacionados à exposição à dioxina com efeitos adversos na reprodução e na espermatogênese. Exposição em desenvolvimento ao TCDD é consistentemente relacionada à diminuição da contagem da cauda epididimal de esperma, mas não apoia a conclusão de que a espermatogênese é afetada. Os mecanismos por trás da diminuição da contagem de esperma epididimal são desconhecidos; no entanto, contestamos que a função epididimal é a chave para efeitos adversos do TCDD