Multigenerational effects

There are critical needs with regard to protecting the environment (Medina, 1996). The use of solvents introduces stresses on ecosystems, ultimately on the global level. More testing for acute human toxicity is needed, but increasingly, researchers will strive to include effects on entire ecosystems, and long-term, multigenerational effects on fertility, reproductive quality, and hormonal functions. Any solvent that leads to environmental problems, that can be persistent, toxic, and bioaccumulative, or any combination of these three attributes, needs to be evaluated (Division, 1996). This... 

Kohidai L, Lajk6 E, Pallinger E, Csaha G (2012) Verification of epigenetic inheritance in a unicellular model system multigenerational effects of hormonal imprinting. Cell Biol bit 36 951-959... 

Human populations have been exposed to POPs by consuming contaminated animal-source foodstuffs. The health effects from exposme of the human population to POPs are likely underappreciated. The POPs are passed in utero from mother to fetus and postnatally to the neonate via breast milk. There is some evidence that adverse multigenerational effects occur (Blanck et al., 2000). The timing of exposure in life stages, from embryo to senility, can be important in the expression of adverse effects. 

FLYNN K M, FERGUSON s A, DELCLOS K B and NEWBOLD R R (2000b) Multigenerational exposure to genistein has no severe effects on maternal behavior in rats. Neurotoxicology. 21 (6) 997-1001. 

Moskalev YI, Lyaginskaya AM, Zalikin GA, et al. 1989. Carcinogenic effects in rat progeny exposed perinatally to radionuclides. In Napalkov NP, Rice JM, Tomatis L, et al., ed. Perinatal and multigeneration carcinogenesis. IARC scientific publications 96. Lyon, France International Agency for Research on Cancer, 421-427. 

Restum, J.C., S.J. Bursian, J.P. Giesy, J.A. Render, W.G. Helferich, E.B. Shipp, D.A. Verbrugge, and R.J. Aulerich. 1998. Multigenerational study of the effects of consumption of PCB-contaminated carp from Saginaw Bay, Lake Huron, on mink. 1. Effects on mink reproduction, kit growth and survival, and selected biological parameters. Jour. Toxicol. Environ. Health 54A 343-375. 

Reproductive toxicity of acesulfame K was studied in test systems aimed at detecting teratogenicity, oral embiyotoxicity and in a multigeneration study. No teratogenicity, no embryotoxicity, and no effects on reproduction, development of the fetuses and lactation performance were found.7... 

However, these effects have been noted in only one study (Mann et al. 1985), and were not seen in the multigeneration study in mice by NTP (Heindel et al. 1989 Morrissey et al. 1989 NTP 1985) or other studies in rats (Lake et al. 1984, 1986 Oishi and Hiraga 1980). 

Renwick et al. (2000) have performed an analysis of the need for an additional UF for infants and children. They considered that the proposal to introduce an additional 10-fold factor when exposure of infants and children is anticipated implies either age-related differences between species or differences within humans, which exceed those present in adults. Alternatively, the extra factor could be related to deficiencies of current testing methods or concerns over irreversibility in developing organ systems. They concluded that the available data did not provide a scientific rationale for an extra factor due to inadequacy of inter- and intraspecies UFs. Justification for the factor therefore must relate to the adequacy and sensitivity of current methods or concern about irreversible effects in the developing organism. They also pointed out that when adequate reproduction, multigeneration, or developmental studies are conducted, there will be no need for an additional 10-fold factor. 

In a multigeneration study of reproductive effects, levels of 500 or 125ppm did not effect fertility, litter production, or litter size and did not cause congenital abnormalities. Lens opacities were found in the parents and Fi and F2 generation receiving 500 ppm, but not at the 12 5 ppm level. 

Reproductive Toxicity. No studies were located regarding the reproductive effects of thorium in humans following exposure by any route. Neither inhalation nor oral reproduction studies in animals were located. Pharmacokinetic data following inhalation or oral exposure were not located to allow the prediction of possible reproductive effects. One dermal rat study found testicular effects after administration directly onto the scrotal skin. Additional inhalation, oral, and dermal reproduction studies and multigenerational studies would be helpful in assessing the potential risk to humans. 

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