Sperm production alterations

Decreases in fertility, altered levels of sex hormones, reduced production of sperm, and increased rates of miscarriages were found in animals exposed to 2,3,7,8-TCDD in food. Rats and mice that were exposed to small amounts of 2,3,7,8-TCDD in food for a long time developed cancer of the liver and thyroid, and other types of cancer. 

Zinc plays a fundamental role in human fertility and reproduction. A crude but indicative piece of evidence in this regard is that semen contains a large amount of zinc and zinc deficiencies are associated with low sperm counts. More formally, the production and development of sperm depends on a zinc-activated protein, human protamine 2 (HP2). Displacing zinc, lead binds itself to HP2 and in the process alters the structure of the protein. Zinc-related processes are also linked to the transcription and translation of human DNA. The genetic code would remain inert if not for its coupling to RNA, which carries the code, as it... 

Products containing infertility causative ageuts iuclude adhesives, paints, siU-cones, solvents, and the fumes from welding rods that emitted during welding [3]. House dust containing organophosphate flame retardants has been shown to alter hormone levels and decrease sperm quality in men [4]. 

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