Maximum acceptable concentrations

What is the maximum acceptable concentration of benzoate if this ion-selective electrode is to be used for analyzing samples containing as little as 10 M salicylate with an accuracy of better than 1% ... 

The maximum acceptable concentration for free (molecular) bromine is 0.1 mg/L for ionic bromate, 100 mg/L. 

According to EPA, "The maximum acceptable concentrations of PCB in any sample consisting of a homogenate of 25 or more whole fish of any species that is consumed by fish-eating birds and mammals, within the size range consumed is 0.5 mg/kg on a net weight basis."... 

This method can be used to determine Hg in waters used for fish far ming, at levels half of maximum acceptable concentration (0.2 J.gi y. 

In the early development of such limits, they were generally known as Maximum Allowable Concentrations or MACs, sometimes called Maximum Acceptable Concentrations, or Maximum Permissible Concentrations. 

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. 

A great many human fatalities associated with acute HCN exposure have occurred, but exposure concentrations are for the most part unknown. Acute exposures that failed to result in mortality were either to high concentrations for very short exposure durations (approximately 500 or 450 ppm for approximately 1.5 min or 6 min, respectively [Barcroft 1931 Bonsall 1984]) or to exposure concentrations and times that were estimated (>25 ppm for about 1 h [Parmenter 1926]). Monitoring studies indicate that workers were routinely exposed at <10 ppm (Hardy et al. 1950 Grabois 1954 Maehly and Swensson 1970). Occupational HCN exposures at 1-10 ppm were acceptable at the time of these surveys as 10 ppm was the maximum acceptable concentration for workers. More effective exhaust ventilation was implemented where re... 

According to guidelines published by the Ontario Ministry of the Environment in January 2001, the Maximum Acceptable Concentration (MAC) for Pb " in drinking water is 0.010 mg/L. The water in a community is contaminated with Pb " from an industrial source, at a concentration of 0.0800 mg/L. 

Maximum acceptable concentration in room air of former Soviet Union Irritation threshold... 

Levels for most metals and organics are well below the maximum acceptable concentrations (MAC) specified in Guidelines for the Canadian Drinking Water Quality (1978). However, the highest level of lead found in some localities is higher (79.7 /xg/L) than the MAC (50 Mg/L). 

All adhesives, solvents, chemical treatments, and like materials must be handled in a manner preventing toxic exposure to the workforce. Methods and facilities must be provided to ensure that the maximum acceptable concentrations of hazardous materials are never exceeded. These values are prominently displayed on the material s Material Safety Data Sheet (MSDS), which must be maintained and available for the workforce. 

Chronic toxicity data are preferred for deriving an annual average EQS (AA-EQS). Acute data are used to calculate a maximum acceptable concentration EQS (MAC-EQS) and can be used to derive the AA-EQS if insufficient chronic data are available, but an AA-EQS should not be derived exclusively on the basis of acute data. Guides to efficient decision making about the testing requirements for derivation of short- and long-term EQSs based on modes of action and other considerations were provided by Verhaar et al. (1992), de Wolf et al. (2005), and Hutchinson et al. (2006). 

Ion or compound Maximum Acceptable Concentration (MAC) (mg/L) Interim Maximum Acceptable Concentration (mg/L) Aesthetic Objectives (A0) (mg/L)... 

The Paul Ehrlich Institut of Germany recalled certain batches of human albumin products (Human Albumin 20%, Human Albumin 20% Immuno, Human Albumin Immuno 20%, Human Albumin 25% Immuno), including batches that had exceeded 12 months of shelf life (22). This action was taken after quality assurance tests had shown that the aluminium content of these batches had exceeded the maximum acceptable concentration of 200 ng/ml. 

In 1990 there were 3 reports of the low level occurrence of benzene in beverages. Bottled mineral water was contaminated with benzene originated from an underground source of carbon dioxide which was inadequately carbon treated [23]. Two manufacturers found benzene in fmit flavoured mineral waters at levels greater than 5.0 pg/kg [24], The US EPA maximum contaminant level (MAE) for benzene is 0.005 mg/L [25] which is also the Canadian guideline as maximum acceptable concentration (MAC) in drinking water [26]. The manufacturers attributed the benzene to the presence of ascorbic acid and sodium benzoate in combination in their drink formations [27], omitting either of these additives eliminated the benzene. 

The establishment of a maximum acceptable concentration of any chemical in potable water should not be done in isolation, but should consider all sources of exposure. Intake of pesticides can result from worker exposure, ingestion, and water exposure. Work-related exposure is time and space limited and is restricted to limited populations which are evaluated in separate studies and are not as all encompassing as food and water exposure. 

The limiting exposure is often expressed in the form of a maximum amount that may be inhaled during a lifetime, as in the case of radiation. This amount is then converted to a maximum acceptable concentration. 

For example, the maximum amount of a-B.P. (a-Benzo Pyrene) that may be inhaled is 12 to 16 mg corresponding to a maximum acceptable concentration of 0.15i. g/m3. 

Methanol on the other hand is very toxic as was recognised quite recently in connection with the adulteration of wines (the ingestion of only a few millilitres can be fatal). Methanol can penetrate into the organism via the lungs or skin. It accumulates in the body and the maximum acceptable concentrations in the absence of periods of non-exposure for the elimination of the poison, is very low (3ppm). 

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