Maximum reportable concentration

A higher concentration of dioctyltin in sewage sludge of 0.56 mg/kg as the chloride is reported by Summer et al. (2003). Thus, the maximum reported concentrations for the individual compounds are as follows ... 

Maximum reportable concentration. The upper limit of measurement for a method is usually defined as the concentration at which the curve shows a certain deviation from linearity. 

Confidence bands are direct precision data, and the maximum reportable concentration can be defined as the maximum concentration at which the method yields adequate precision ( ) (excluding measurements near the minimum reportable concentration, where poor precision is unavoidable). Table III shows RCB for the determination of iron in water by AAS. The analyst may consider a RCB of say, 15% to be adequate. The maximum reportable concentration would be 15 pg/ml from a single, weighted least-squares curve, and 20 pg/ml by the multiple-curve method. Samples containing > 20 pg/ml should be diluted to 1-10 pg/ml and analyzed using standards containing 0.05 - 15 pg/mL. (Note that it is always better to include a standard above the maximum desired concentration. The precision of this standard measurement will be poor, but poor data at this level are better than none.)... 

PAHs have been detected in urban runoff generally at concentrations much higher than those reported for surface water. Data collected as part of the Nationwide Urban Runoff Program indicate concentrations of individual PAHs in the range of 300-10,000 ng/L, with the concentrations of most PAHs above 1,000 ng/L (Cole et al. 1984). In a recent study by Pitt et al. (1993) which involved the collection and analysis of approximately 140 urban runoff samples from a number of different source areas in Birmingham, Alabama, and under various rain conditions, fluoranthene was one of two organic compounds detected most frequently (23% of samples). The highest frequencies of detection occurred in roof runoff, urban creeks, and combined sewer overflow samples. The maximum reported concentration of fluoranthene in these samples was 130 jag/L. 

Table I shows the maximum reported concentrations of CAA fi om recent literature. Figure 1 shows the thermal distribution of CAA from recently published analyses. The maximum concentrations are from water samples from basins presently undergoing intense CAA generation and expulsion (1.7.10.16.17.32.35.41.42.43.44.45).

Table I. MAXIMUM REPORTED CONCENTRATIONS OF CARBOXYLIC ACID ANIONS IN PRODUCED FORMATION WATERS...

Table 2 Overview of maximum reported concentrations (expressed in xg L ) of MTBE and related compounds in different environmental water bodies by different analytical methods over the last decade in comparison with EU project (WATCH and P-THREE) results... 

Type Maximum Reported Concentration Advantages Disadvantages References... 

However, we have to criticize more specifically the paper by Lown et al. (1984), who characterized alkanediazonium ions, as well as (E)- and (Z)-alkanediazoate ions, by 15N NMR spectroscopy. They also report NMR data on the (E)- and (Z)-benzenediazohydroxides as reference compounds, describing the way they obtained these compounds in only three lines. Obviously the authors are not familiar with the work on the complex system of acid-base equilibria which led 30 years earlier to the conclusion that the maximum equilibrium concentration of benzenediazohydroxide is less than 1 % of the stoichiometric concentration in water (see Ch. 5). The method of Lown et al. consists in adding 10% (v/v) water to a mixture of benzenediazonium chloride and KOH in dimethylsulfoxide. In the opinion of the present author it is unlikely that this procedure yields the (Z)- and CE>benzenediazohydroxides. Such a claim needs more detailed experimental evidence. 

NCRP (1953). National Committee on Radiation Protection and Measurements, Maximum Permissible Amounts of Radioisotopes in the Human Body and Maximum Permissible Concentrations in Air and Water, NCRP Report No. 11, published as National Bureau of Standards Handbook No. 52, Superseded by NCRP Report No. 22 (National Council on Radiation Protection and Measurements, Washington). 

Our HBCD results were consistent with reported data for river sediments. Sellstrom et al. [29] reported concentration levels between nd and 1,600 ng/g dw in river sediments from a Swedish river with numerous textile industries. Morris et al. [18] determined HBCD in river and estuarine sediment samples. HBCD was detected in all sediments analyzed. The maximum value for total HBCD... 

Data are scarce in mammals that link zinc concentrations in tissues with environmental zinc perturbations. In harbor porpoises, impaired homeostasis reportedly occurs when zinc exceeds 100 mg/kg FW liver however, livers of many species of marine mammals routinely exceed this value (Wood and Van Vleet 1996). Elevated zinc concentrations, in mg Zn/kg DW tissue, were >120 in cattle liver, >180 in sheep kidney, and >250 in sheep liver (Table 9.9), but their significance is unclear. No international regulations or guidelines applicable to zinc are available (USPHS 1989). No U.S. Food and Drug Administration action level or other maximum acceptable concentration exists for zinc, and therefore no Final Residue Value can be calculated (USEPA 1987). This seems to be a high priority research need. 

As informed Dr. A.I. Korableva from Institute for Environmental Management and Ecology under the National Academy of Sciences of Ukraine in the report "Environmental impact of automobile transport by example of Dnepropetrovsk", Dnepropetrovsk with its annual discharge of air pollutants of 177,000 t (as of 1996) is among the worst affected cities in Ukraine. In these, the automobile transport was found to be responsible for at least 30 % of the total emissions which are 15 times the maximum permissible level. Aside from the dust, chemical, photochemical and noise pollution, there is the aspect of street washout of automobile-related pollutants into the River Dnieper. The measured annual receipts of lead, particulates and petroleum derivatives via rainwater and thaw water to the river are 0.45, 80,000+ and 1.8+ t respectively. The actual levels of petroleum derivatives in storm water sometimes were 206 times the maximum permissible concentration (MPC) for the fishery basins. At 34 km downstream from the city, the estimated levels of petroleum derivatives and particulates are 61 and 10.8 times the respective MPCs. The airborne lead is mainly accumulated in the soil of housing areas. 

Minimum explosive concentration for explosive and pyrotechnic dusts have been reported in the range of 40 to 1000 gm/mm, (40 to 1000 oz/ft ). With the exception of location 5 in Building 1619 at Louisiana AAP, all the dust concentrations determined for the various plants were below the maximum average concentrations. 

Limited information was found on atmospheric concentrations of endrin between 1970 and the mid-1980s, prior to cancellation of virtually all uses (Bishop 1984, 1985, 1986 EPA 1993e USDA 1995) (see Section 4.3). The data were insufficient to identify any trends. The mean and maximum airborne concentrations of endrin in the United States in 1970-71 were reported to be 0.2 ng/m3 and 19.2 ng/m3, respectively (Lee 1977). For that same time period, mean airborne concentrations at suburban sites near Jackson, Mississippi, and Columbia, South Carolina, were reported to be 0.1 ng/m3 and 0.2 ng/m3, respectively (Bidleman 1981 Kutz et al. 1976). Endrin was not detected at Boston, Massachusetts, suburban sites... 

More recently, Petrovic et al. [9] reported NP sediment concentrations of <0.01-0.45 p.g g-1 at the coast of Barcelona, using LC-MS analysis. Other sites along the Spanish coast showed a maximum NP concentration of 1.05 p.gg-1 at a site in the proximity of the outflow of partially untreated wastewater. AEs were detected between 0.037 and 1.30 p.gg-1, and curiously, the supposedly easily biodegradable CDAs were detected in all sediment samples, in the range of 0.03-2.71 mg g-1. 

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