Chronic studies, fish

BPA is considered an endocrine disruptor chemical and, in chronic studies, induces production of vitellogenin in male fathead minnows (P. promelas) at concentrations of 640 and 1280pgl after 43 days and 160pgl after 71 days. Induction of vitellogenin is a process normally occurring only in female fish in response to estrogenic hormones during the reproductive cycle. 

Aquatic organisms Acute test fish (2x) and Daphnia, long-term/chronic test fish and Daphnia, algae, aquatic plant for herbicides, sediment organisms, bioaccumulation study Mainly a.i. tests... 

The PNEC value is obtained by dividing the acute toxicity value for the most sensitive species (i.e. the lowest of IC50 for algae, EC50 for Daphnia and LC50 for fish) identified in ecotoxicity studies by a large assessment factor. If data from chronic studies with fish or Daphnia are available, the assessment factor is reduced. 

Monomethyltirf. Acute toxicity studies were identified for monomethyltin for algae, invertebrates, and fish. Chronic NOECs were available for algae and invertebrates. A chronic NOEC of 0.007 mg/1 for monomethyltin chloride in Scenedesmus subspica-tus was the lowest reported result. Since there were no long-term test results available for fish, it was necessary to apply an uncertainty factor of 50 to the critical study. 

Dioctyltirv. Acute toxicity studies were identified for dioctyltin for invertebrates and fish. Chronic NOECs were available for algae and invertebrates. 

Chronic toxicity evaluation of wastewater and treatment-plant effluents a 170 comparison between BL bacterial, invertebrate, and fish assays General or basic studies... 

The case study of Flix is another well-documented concern about fish that are chronically impacted by Hg throughout a chlor-alkali plant. Here, we review all the data available about the reported levels of Hg. A description of the biological effects is not the aim of this chapter and will not be covered, but we will mention whether or not these effects exist. 

This area was the most profusely studied in the AQUATERRA project in terms of biological effects in fish populations. Barbel and bleak were the sentinel species selected in this area and an array of histological and biochemical tests were used to monitor the impact due to three major sources of pollution mercury and OCs at Monzon (with a comparison in one of the papers with Flix) and PBDEs in Barbastro [1—4, 37]. Mercury pollution was directly correlated to an increase of MTprotein in the liver of barbel captured downstream Monzon when compared to samples captured upstream (Fig. 3a). However, mRNA quantitative analyses failed to show any differences between downstream and upstream Monzon, neither correlated with MT protein levels. Further studies showed that MT mRNA in liver is a rather weak marker for chronic metal pollution in liver (see below) [4], The presence of degenerative hepatocytes in barbels and bleaks was also linked to mercury poisoning although it can also reflect the impact by other pollutants, like OCs or PBDEs (Fig. 3e). 

In vivo mutagenicity studies Further repeat-dose study in the rat Second developmental toxicity study Two-generation fertility study in the rat Chronic fish toxicity study Biodegradation simulation studies... 

From the human perspective, HABs are problematic because they cause (1) risks to human health, (2) loss of natural or cultured seafood resources, (3) impairment of tourism and recreational activities, and (4) damage to noncommercial marine resources and wildlife. Exposure pathways include (1) consumption of toxic shellfish that have accumulated phytoplankton toxins filtered from the water, (2) consumption of tropical fish that have accumulated phytoplankton toxins (ciguatera), (3) inhalation of aerosolized toxins ejected from the sea surface, and (4) skin contact resulting in irritations due to allergy-like reactions. Harmful health effects from acute exposures have been relatively well studied. Less well known are the health effects resulting from chronic exposures to low toxin levels. This is of particular concern with regards to marine mammals and seabirds. 

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