An assessment of polybrominated diphenyl ethers (PBDEs) in sediments and bivalves of the U.S. coastal zone

NOAA’s Mussel Watch Program was designed to monitor the status and trends of chemical contamination of U.S. coastal waters, including the Great Lakes. The Program began in 1986 and is one of the longest running, continuous coastal monitoring programs that is national in scope. NOAA established Mussel Watch in response to a legislative mandate under Section 202 of Title II of the Marine Protection, Research and Sanctuaries Act (MPRSA) (33 USC 1442). In addition to monitoring contaminants throughout the Nation’s coastal shores, Mussel Watch stores samples in a specimen bank so that trends can be determined retrospectively for new and emerging contaminants of concern. In recent years, flame retardant chemicals, known as polybrominated diphenyl ethers (PBDEs), have generated international concern over their widespread distribution in the environment, their potential to bioaccumulate in humans and wildlife, and concern for suspected adverse human health effects. The Mussel Watch Program, with additional funding provided by NOAA’s Oceans and Human Health Initiative, conducted a study of PBDEs in bivalve tissues and sediments. This report, which represents the first national assessment of PBDEs in the U.S. coastal zone, shows that they are widely distributed. PBDE concentrations in both sediment and bivalve tissue correlate with human population density along the U.S. coastline. The national and watershed perspectives given in this report are intended to support research, local monitoring, resource management, and policy decisions concerning these contaminants.

Biodeterioration of wooden boats: a major problem facing marine fisheries

In India, the fishing industry alone incurs an annual loss of over 120 million rupees on account of biodeterioration of wooden fishing craft. None of the timber species, currently in demand for boat-building, possesses an natural bioresistance and will be completely destroyed within 6 to 12 months. Preventive measures against biodeterioration range from application of several indigenous formulations to metallic sheathings and pressure impregnation of wood with preservative chemicals. These methods do not provide lasting protection, as each has its own short-comings and inadequacies. The need for long-term research in the field of marine biodeterioration for improving the efficiency of currently known control measures, with emphasis on application of non-polluting biological methods, is stressed.

Use of different glazes in frozen oil sardines

This paper reports on the relationship between the seasonal variations in the oil content of the Indian oil sardines (Sardinella longiceps) and their frozen storage life at -l8°C and on the use of various chemicals and coating materials to extent their storage life. It is observed that there is an inverse relationship between the oil content and the frozen storage life- oil content varying from 10.33 to 42.43% (MFB) and storage life from 2 to 5 months. Extension of storage life is achieved by dipping in hydroquinone solution prior to freezing or by coating with agar after freezing. Data on changes in peroxide value, free fatty acids, moisture, drip and organoleptic characteristics during frozen storage are presented.

Toxicity of four therapeutic compounds to fry of Indian major carps

Toxicity of four therapeutic compounds: sodium chloride, potassium permanganate, potassium dichromate and acriflavine to fry of Catla calla, Labeo rohita and Cirrhinus mrigala was tested. Bioassays were conducted in 5 and 10 liters glass jars in the laboratory for periods of 24-48 hrs. at temperatures of 26° and 32°C. LC 50 values of the chemicals were in the ranges of 5500 to 7500 ppm, 37.5 to 48 ppm, 92.5 to 125 ppm and 47.5 to 80 ppm respectively. The results obtained are of value in evolving cheap control methods against some common fish diseases. Sodium chloride and acriflavine can be widely used for chemotherapy and potassium dichromate is preferable to potassium permanganate for prophylaxis.

Studies on the storage behaviour of laminated and commercial Bombay duck

A modified method for the preparation of laminated Bombay duck is presented. Investigation was carried out to find out an effective chemical to control the discoloration of dried laminated Bombay duck. Among various chemicals tried, NDGA and BHT were found to have considerably retarded the discoloration and extended the storage life of the product. Attempt was also made to suggest the optimum humidity level for the proper storage of the commercially dried fish. It was found that a level of about 65% R. H. provided maximum storage life to commercial product.

Acute toxicity of chlorpyrifos, cadusafos and diazinon to three Indian major carps (Catla catla, Labeo rohita and Cirrhinus mrigala) fingerlings

Fingerlings of three Indian major carps, viz. Catla catla (Hamilton-Buchanon), Labeo rohita (Hamilton-Buchanon) and Cirrhinus mrigala (Hamilton-Buchanon), were exposed to different concentrations of chlorpyrifos (lorsban 10 G), cadusafos (rugby 10 G) and diazinon (basudin 10 G) for a period of 96h with a view to determine the median lethal concentrations (LC sub50) values for each of chemicals. Of the tested concentrations, chlorpyrifos at a dose of 6.65 ppm, cadusafos at 2.0 ppm and diazinon at a dose of 8.40 ppm or above induced 100% mortalities within 96h of exposure. The 96h LC sub50 values of chlorpyrefos, cadusafos and diazinon were 1.66, 0.72 and 2.10 ppm for C. catla, 2.35, 0.72 and 2.97 for L. rohita and 2.35, 0.72 and 2.10 ppm for C. mrigala, respectively. Pesticide induced behavioral abnormalities observed in the present study included erratic movements, rapid operculum activities, jumping of fish out of the test media, violent spasm and convulsion.

Selected trace metal concentration in bottom water and sediments of Kyoga basin lakes, and its potential to aquatic pollution

Although other research studies on areas such as the physical-chemical, nutrients and phytoplankton status of Lake Kyoga systems have been given a lot of attention (e.g. Mungoma 1988 and NaFIRRI 2006), efforts to determine the pollution status of this system, especially by heavy metals as one of the worldwide emerging environmental problems, is still limited. Many trace metals are regarded as serious pollutants of aquatic ecosystems because of their persistence, toxicity and ability to be incorporated into food chains (Mwamburi J., and Nathan O.F., 1997). Given the rapid human population growth and the associated economic activities both within the rural and urban areas in Uganda, such fish production systems are becoming very prone to various kinds of pollution including that by heavy metals. Anthropogenic factors such deforestation, use of chemicals and dumping of metallic products, spillages of fuels from outboard engines and many others and or natural processes involving atmospheric deposition by wind or rain, surface run-offs and streams flows from the catchment introduces heavy metals into the lake environment,.

Disease problems in shrimp sector in Khulna district of Bangladesh: a question of sustainability

Disease is the main restraining factor for the development of shrimp sector in Bangladesh. Both brackish water shrimp bagda (Penaeus monodon) and freshwater prawn golda, (Macrobrachium rosenbergii) farming in Bangladesh have been facing disease problem. A study on disease outbreak in both brackish water and freshwater small-scale shrimp farms (gher) in Khulna district was carried out through interviewing randomly selected 3-5% of shrimp farmers with a structured questionnaire during March to December, 2002. The study showed that 97% bagda farming ghers and 80% golda farming ghers were affected by disease. White spot disease was the severe disease for bagda, whereas, antenna rot was the main disease for freshwater prawn. Change of water and liming were carried out as control measures of disease for bagda shrimp farming, while it was only liming for golda farming. A small number of shrimp farmers (15%) used chemicals for treatment of shrimp diseases. Development of suitable farming technology to prevent disease contamination and innovation of proper treatments for diseases are required to overcome the disease problems for sustainable shrimp farming in Bangladesh.

Studies on the toxicological effects of Asulox-40 and Emisan-6 to eggs and early life history stages of Sarotherodon mossambicus

Toxicological effects of Asulox-40 and Emisan-6 to eggs and early life history stages of Sarotherodon mossambicus were reported. 80% of egg hatching occurred in the controls, 1 p.p.m and 5 p.p.m concentrations of Asulox-40. 10 p.p.m. and 50 p.p.m. concentrations of the same toxicants had 70% and 60% hatchings while in Emisan-6 in the same concentrations the hatching were 70% and! 40%. In 100 p.p.m. concentration of both toxicants 20% incomplete hatching occurred. In Emisan-6 Lc 50 and Lc 100 values were recorded at 32 hand 96h respectively in 10 p.p.m. concentrations. In Asulox-40 the same values were recorded in 24h and 40h respectively at 50 p.p.m. concentration. The fish activity during the experimental period showed initial hyper activity. It was established that the Emisan-6 is more harmful to S. mossambicus than Asulox-40. The harmless concentrations of these chemicals were 1.2 p.p.m. for Asulox-40 and 0.6 p.p.m. for Emisan-6.

Viability of frozen algae used as food for larval penaeids

Freezing with added chemicals as flocculants and protectants was assessed as a means of preserving stock cultures of 4 algal species used for larval penaeid food Chaetoceros calcitrans, Skeletonema costatum, Tetraselmis chuii and Isochrysis galbana . The maximum storage effectability of the preservation techniques for each species was also determined.

In-vitro effect of fungicides on hyphal growth and sporogenesis of Lagenidium sp. isolated from Penaeus monodon larvae and Scylla serrata eggs

The sensitivity of Lagenidium, isolated from Penaeus monodon, Scylla serrata , to 34 antimycotics was determined. Effects on the development of vesicles, zoospores and mycelial growth were evaluated. Although mycoidal levels of the chemicals tested will be ideal for lethal treatment on control of the fungus, the high dose required may be lethal to the host, thus the use of mycostatic concentrations is more practical. Treatments of rearing water containing larvae, adult shrimps or crabs should be done only after preliminary tolerance experiments using at least the mycostatic dose prove to be safe for the hosts. Mycocidal doses can be used for determining disinfection doses of equipment and facilities used in rearing procedures as well as for destroying batches of infected larvae.

Viability of frozen algae used as food for larval penaeids

Freezing with added chemicals as flocculants and protectants was assessed as a means of preserving stock cultures of 4 algal species used for larval penaeid food Chaetoceros calcitrans, Skeletonema costatum, Tetraselmis chuii and Isochrysis galbana. The maximum storage effectability of the preservation techniques for each species was also determined.

The trouble with antibiotics and pesticides is...

The paper discusses the output of the meeting on the use of chemicals in aquaculture in Asia. The effects of chemical use on cultured stocks in the farm, the immediate environment through discharges and effluents, surrounding areas, farm staff, consumers and drug resistance organisms are also discussed. It also shows how an antibiotic-resistant microorganism develops as the result of indiscriminate use of antibiotics.

Ecological impacts of coastal aquaculture developments

The study presents the type and scale of any ecological change associated with coastal aquaculture development. These are enrichment, interaction with the food web, oxygen consumption, disturbance of wildlife and habitat destruction, interaction between escaped farmed stock and wild species, introduction and transfers, bioactive compounds (including pesticides and antibiotics), chemicals introduced via construction materials, and hormones and growth promoters.

Future drugs from the sea

The article presents several marine chemicals that are likely candidates for future drugs. There sources and applications were also discussed.