Fish protection

Influence of Fish Protection Considerations on the Design of Cooling Water Intakes... 

Stringent regulatory requirements in the United States often require the incorporation of fish protection facilities at power plant intakes. There are three different concepts that can be used fish collection and removal, fish diversion, and fish deterrance. The incorporation of fish protection systems at specific sites can necessitate modifications to conventional intake designs. Such modifications can influence screen-well layouts and selection of screens and pumps, and in certain cases require model studies to develop design criteria which will ensure that fish protection facilities will be biologically effective and not adversely affect plant operations. 9 refs, cited. 

The xylenes are mildly toxic. They ate mild skin irritants, and skin protection and the cannister-type masks are recommended. The oral LD q value for rats is 4300 ppm. The STEL for humans is 150 ppm. Xylenes show only mild toxicity to fish, and the threshold limit for crop damage is 800—2400 ppm. Biodegradation with activated seed is slow, and sewage digestion is impaired by 0.1% concentrations. In the event of a spih, oil-skimming equipment, adsorbent foam, and charcoal maybe used for cleanup. 

Citric acid is used in carbonated beverages to provide tartness, modify and enhance flavors, and chelate trace metals. It is often added to jams and jellies to control pH and provide tartness. It is used in cured and freeze-dried meat products to protect the amino acids (qv) and improve water retention. Bakers use it to improve the flavor of fmit fillings in baked goods. Because citric acid is a good chelator for trace metals, it is used as an antioxidant synergist in fats and oils, and as a preservative in frozen fish and shellfish (7) (see Antioxidaisits). 

Vegetable and seed oils as well as some synthetic base stocks present a new class of biodegradable base stocks. These fluids (10) have excellent biodegradation properties as measured by criteria developed by the Environmental Protection Agency (EPA) or Organization of Economic Cooperation and Development (OECD). OECD 301 and EPA 560/6-82-003 measure the biodegradation of lubricants. These tests were developed to measure the degradation of oil, especially two-cycle ok, on waterways. Aquatic toxicity criteria toward fish is also found to be acceptable for this class of fluids as measured by EPA 560/6-82-002 and OECD 203 1-12. 

According to NAS, "Fish-eating birds should be protected if mercury levels in fish do not exceed 0.5 mg/g."... 

When it approved the New Animal Drug AppHcation (NADA) of formalin, FDA ruled that use of formalin for fisheries was safe for humans and the environment. They ruled that effluents from fish treatments at 250 mg/L should be diluted 10 times and from egg treatments 75 times if 1,000 —2,000 mg/L were used (10,11). Before registering the compound, FDA also addressed carcinogenicity by stating it was not concerned about human exposure from either water or fish treated with formalin. The U.S. Fish and Wildlife Service (USFWS) has procedural guidelines that should protect workers from harm fill levels of formalin. Calculations based on treatment levels demonstrated that a fishery worker is exposed to not more than 0.117 mg/L formalin in the air, well below the levels estabUshed by the U.S. Occupational Safety and Health Administration to protect workers. 

States have made substantial recent progress in the adoption, and EPA approval, of toxic pollutant water-quahty standards. Furthermore, virtually all states have at least proposed new toxics criteria for priority toxic pollutants since Section 303 (c) (2) (B) was added to the CWA in February of 1987. Unfortunately, not all such state proposals address, in a comprehensive manner, the requirements or Section 303 (c) (2) (B). For example, some states have proposed to adopt criteria to protect aquatic hfe, but not human health other states have proposed human health criteria that do not address major exposure pathways (such as the combination of both fish consumption and drinking water). In addition, in some cases final adoption or proposed state toxics criteria that would be approved by EPA has been substantially delayed due to controversial and difficult issues associated with the toxic pollutant criteria adoption process. 

Measurement of contaminants in fish has concentrated on muscle tissue since the aim has generally been to protect the health of the consumer rather than that of the fish. Endocrine tissue such as the gonads has been much more rarely examined, while data for adrenal, thyroid and pituitary levels are virtually non-existent. More data are available for the liver, as a lipid rich tissue and the major site of xenobiotic catabolism, but the concentrations have rarely been related to its capacity to produce vitellogenin or metabolise endogenous hormones. Tissue concentrations of a wide range of chemicals, are at a level which suggests that, either alone or in combination, they will cause significant endocrine disruption in fish in many polluted habitats. 

A surface coating protects the substrate against abrasion, moisture, light, and corrosion. The binder for the pigment and extenders is fluid before application and rigid soon after. Natural binders range from gum arable to fish oil. The first varnishes were solutions of natural resins, having transparency, hardness, amorphous structure, and little permanence. 

The Northwest Power Plamimg Council designates 44,000 miles of Northwest streams as protected areas because of their importance as critical fish and wildlife habitat. 

By some estimates, fish and wildlife protection measures reduced firm electric generation by about 850 megawatts annually. 

Fish which is frozen in air blast will often be dipped into clean water afterwards, resulting in a layer of ice on the surface. This glazing process protects the fish from the effects of dehydration in subsequent storage. 

Fish and Shellfish. Sardines in oil and also in tomato sauce and mustard sauce are packed commercially in enameled aluminum cans. However, tomato and mustard sauces are corrosive products that can attack metal containers. Sardines prepared in these sauces should not exceed 3.0% total acidity, expressed as acetic acid. Otherwise, the presently used interior can enamels will not protect the food sufficiently to prevent chemical reactions with the metal. 

Concentrations of PCBs in fish from each of the Great Lakes currently exceed the GLWQA objectives for the protection of aquatic life. Similarly, concentrations of some substances (e.g., PCBs, Hg, mirex, toxaphene) in Great Lakes fish continue to exceed acceptable guidelines for human consumption. Documented effects in the Great Lakes include reproductive failure, congenital abnormalities and induction of tumours in various aquatic, terrestrial and avian species (23). 

Toxicity Test (Bioassay). Organisms representative of those to be protected are exposed to the test water under rigorously controlled conditions, usually in a laboratory environment. In this test the organisms, normally fish, are exposed for a standard time period in aquaria to various dilutions of waste or river water while some physiological parameter is carefully monitored to determine fish response. Behavior is also observed. 

The federal government has set standards and guidelines to protect people from the possible adverse health effects of endosulfan in drinking water and food. EPA recommends that the amount of endosulfan in lakes, rivers, and streams should not be more than 74 micrograms per liter (pg/L) or 74 parts per billion (74 ppb). This should prevent any harmful health effects from occurring in people who drink the water or eat fish or seafood that live in the water. FDA allows no more than 24 parts per million (24 ppm) of endosulfan on dried tea, and EPA allows no more than 0.1 to 2 ppm endosulfan on other raw agricultural products. 

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