Osaka Bay

Watanabe et al. (1987) detected PBDEs in numerous marine fish and shell fish in Japan. TeBDE and PeBDE levels ranged from 0.1 and 17 ng/g fresh weight, with TeBDE being the major congener. DeBDE was also detected in a mussel sample from Osaka Bay (at 1.4 g/kg wet weight). Recently, Japanese market fish were analyzed for PBDEs. The highest combined PBDE levels (BDE-28, -47, -99, -100,... 

Figure 1.3. p,p DDE levels (average of five specimens data in each location) in fishes (Sea bass) in Tokyo Bay, Osaka Bay and Seto Inland sea between 1978 and 2000. 

Similar trends are also observed in PCB levels in Sea bass in the three coastal water environments as shown in Fig. 1.4. Again a clear decreasing trend was seen in Seto Inland sea, while the levels in Tokyo Bay are rather flat with a couple of fluctuations. The time trend in Osaka Bay is more or less similar to Tokyo Bay but with no clear decrease in recent decades. The difference between / ,//-DDE and PCB time trends in Osaka Bay might reflect either the difference in recent loading of the compounds to the Bay or the difference in their pollution histories. 

Figure 13. Towed pressure vessel being lowered into Osaka Bay.

Tokyo and Osaka Bays (metals, PAH, fuel oil, coprostanol)... 

Simidu, U. (1 994) Characterization of microbial community structure in the surface sediment of Osaka Bay, Japan, by phospholipid fatty acid ana lysis. Applied and Environmental Microbiology 60, 248-257. 

Relatively little is known about antimony in the marine environment. It may require a closer look if an input from mining or flame retardant production was anticipated. Water in Osaka Bay contained antimony at 0.15 pg/1, with one sample as high as 0.8 pg/1. Higher concentrations were reported for fresh and rain water [86]. Since, historically, many major pollution problems started in Japan (Minamata - mercury, itai-itai - cadmium, yusho - PCBs), these findings may well be an advance notice to initiate a survey of antimony in the marine environment. 

Relatively Httle is known about industrial organophosphates, such as triphenyl phosphate, trioctyl phosphate, and tris(chloropropyl) phosphate. These compounds are used as plasticizers and flame retardants and are likely to reach the marine environment. Six organophosphates were detected in the water of Osaka Bay in concentrations ranging from 0.1 pg/1 to 1.3 pg/1. The compounds tris(2-chloroethyl)phosphate and tributyl phosphate were the most abundant [144]. 

Tsuchiya, Y. Kawata, Y. 1981. Risk to life, warning systems, and protective construction against past storm surges in Osaka Bay. Journal of Natural Disaster Science 3(2) 27-60. 

To verify the effectiveness of the proposed model, a simulation was carried out for the Osaka Bay area. The proposed model was found to be effective in quantifying navigation safety throughout an entire ship route in Osaka Bay. This model can be helpful to vessel traffic centers and port safety authorities in ship navigation safety management. 

Figure 3. Traffic rules in Osaka Bay (From port authority in...

Figure 4. Observation point for each section in Osaka Bay for safety evaluation of whole ship route area...

Figure 5. Safety index of each section in Osaka Bay at 15 10 on February 3, 2013...

As shown in Figure 1, the ojjeration area is connected to Osaka Bay by the east opening of the Seto Inland Sea. Thus, there is a lot of maritime traffic, and it is also a popular place for catching sea bream, octopus, sand lance, etc. Recommended sea lanes have also been established, and there is concentrated maritime traffic through the area. 

Heterosigma-glycolipids are a series of galactosyl diac-ylglycerols isolated from the Japanese species Heterosigma akashiwo, collected in Osaka bay and cultured in artificial seawater. They all possess n-3 polyimsaturated fatty adds residues 18 4(n-3), 18 5(n-3), and 20 5(n-3) (Kitagawa, Hayashi, and Kobayashi, 1989 Kobayashi et al., 1992). 

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