Blood levels indicator

Umbilical cord blood levels of cadmium tend to be 40%-70% of maternal blood levels, indicating that the placenta provides an incomplete barrier to fetal cadmium exposure. However, one study has shown a positive correlation between maternal blood cadmium levels and placental cadmium concentration. Human infants are born with very low tissue levels of cadmium. 

Disulfiram is usually given orally. Because there is an increased risk of side effects and toxic hazards as the dosage is increased, the daily dosage prescribed in the United States has been limited to 250—500 mg/day. However, efforts to titrate the dosage of disulfiram in relation to a challenge dose of ethanol indicated that some patients require in excess of 1 g/day of disulfiram to reach blood levels sufficient to produce a DER (Brewer 1984). 

Dekant et al. 1986b Filser and Bolt 1979 Prout et al. 1985). Male mice can metabolize inhaled trichloroethylene to a greater extent than male rats (Stott et al. 1982). In this study, virtually 100% of the net trichloroethylene uptake by mice was metabolized at both 10- and 600-ppm exposure concentrations, and there was no evidence of metabolic saturation. In rats, however, 98% of the net trichloroethylene uptake from the 10-ppm exposure was metabolized, but only 79% was metabolized at the 600-ppm exposure level. This suggested an incremental approach to the saturation of metabolism in this exposure range in the rat. Rats exposed by inhalation to trichloroethylene concentrations of 50 or 500 ppm for 2 hours showed metabolic saturation at 500 ppm (Dallas et al. 1991). This was indicated by the fact that the trichloroethylene blood levels of the 500-ppm animals progressively increased over the 2-hour period, rather than approaching equilibrium after 25 minutes, as was the case at 50 ppm. 

Three of five men, who lost consciousness within a few minutes of entering a partially drained underground liquid manure storage tank, died before reaching the hospital autopsy showed that two had massive liquid manure pulmonary aspiration, while the third had fulminant pulmonary edema without manure aspiration (Osbem and Crapo 1981). Markedly elevated heart-blood sulfide-ion levels indicated significant hydrogen sulfide exposure. Air samples analyzed about a week after the accident detected only 76 ppm of hydrogen sulfide, but the study authors noted that the environmental conditions were probably different (e g., warmer weather, less-concentrated manure). 

Suggestive evidence of a lead-related decrease in hearing acuity in children has been reported by Robinson et al. (1985) and Schwartz and Otto (1987, 1991). Hearing thresholds at 2,000 Hertz increased linearly with maximum blood lead levels, indicating that lead adversely affects auditory function. The PbB levels in 75 asymptomatic black children, 3-7 years old, ranged from 6 to 59 tg/dL (mean,... 

Hydralazine hydrochloride is rapidly metabolized and excreted. Experiments with carbon-14 labeled drug in humans indicated that less than 10 percent of the intact drug was excreted (36). Within 5 days after a dose, 83 to 89 percent was excreted in the urine and 9 to 12 percent in the feces. Of the material excreted in the urine, 96 percent was recovered in the first 24 hours. Individuals who are slow acetylators exhibit higher hydralazine blood levels than fast acetylators, for the same dose (37) ... 

Time scaling may not be applicable to halogenated hydrocarbons as blood concentrations of these chemicals do not increase as exposure time is increased beyond 5-10 min (Bakshi et al. 1998). In the Utell et al. (1997) study with human volunteers exposed to HCFC-141b, the relationship between exposure concentration and blood level was linear and reached equilibrium at 250 ppm within 145 min. Graphical representation of the exposure time-blood concentration indicated that at the higher concentrations, equilibrium was approached at 225 min, and at 55 min concentrations were within 80% of the 225 min concentration. Furthermore, the circulating HCFC-141b concentration, rather than duration of exposure, defines whether or not a cardiac response will occur. 

In cyanide-poisoning cases, any blood levels of cyanide >0.2 pg/L indicate atoxic situation (Berlin 1977). However, because cyanide binds tightly to cytochrome c oxidase, serious effects can also occur at lower levels therefore, the clinical condition of the patient should be considered when determining proper therapy. 

There are medical tests to determine whether you have been exposed to chlordecone and/or its breakdown product, chlordecone alcohol. Levels of chlordecone and/or chlordecone alcohol can be measured in blood, saliva, feces, or bile. Chlordecone levels in blood are the best indicator of exposure to chlordecone. Since chlordecone remains in the blood for a long time, the test is useful for a long time after exposure has stopped. Chlordecone can be detected in saliva only within the first 24 hours after exposure therefore, this test has limited use. Blood levels of chlordecone are a good reflection of total body content of chlordecone. However, the test is an unsatisfactory indicator of the amount of chlordecone to which you have been exposed because you cannot be sure how much chlordecone left your body between the time you were exposed and the time the test is performed. These tests cannot predict how your health may be affected after exposure. The tests are not done in routine medical examinations, but doctors can collect body fluid samples and send them to a university medical center or a medical laboratory for analysis. Refer to Chapters 2 and 6 for more information. 

When utilization tests were run on a group of 18 male and 7 female human subjects, wide variations in blood level responses were found, particularly among the males.36 [Both in animals (rats) and humans the two sexes respond somewhat differently.] When 134,000 ig. of vitamin A in four different forms, viz., vitamin A alcohol, vitamin A acetate, vitamin A natural ester No. 1, and vitamin A natural ester No. 2, was fed to the group of 18 males on four different occasions, the serum levels found after 6 hours ranged from 178 to 1423 ig. per 100 ml., 122 to 1170 ig. per 100 ml., 110 to 1183 ig. per 100 ml., and 114 to 1230 ig. per 100 ml., respectively. These nearly 10-fold variations in serum levels do not, of course, indicate 10-fold variation in need, but they do show that the vitamin when given in relatively large doses does behave very differently in different individuals. 

A number of clinical tests are available to detect kidney damage. The clinician examining a patient or the toxicologist monitoring an animal toxicity stndy collects urine and blood samples. Indications of kidney damage (which, of course, for the human patient could be related to many factors other then chemical toxicity) include urinary excretion of excessive amonnts of proteins and glucose, and excessive levels in the blood of unexcreted waste products such as urea and creatine. A number of additional kidney function tests are available to help pin down the location of kidney dysfunction. 

Experiments in mice, rats, and monkeys indicate that oral doses (60 mg/kg) of " C-labeled chloroform in olive oil were almost completely absorbed as indicated by a 80-96% recovery of radioactivity in expired air, urine, and carcass (Brown et al. 1974a Taylor et al. 1974). Absorption in mice and monkeys was rapid the peak blood levels were reached 1 hour after oral administration of 60 mg/kg chloroform in olive oil. 

No biomarker of effect that can be associated quantitatively and directly to chloroform exposure has been identified (see Section 2.5.2). If biomarkers of effect were available for this compound and a correlation between the level or intensity of the biomarker of effect and the exposure level existed, it could be used as an indication of the levels and extent of chloroform exposure. However, in cases where an exposure to chloroform has been known to occur, measurements of chloroform in breath or blood can indicate body burden. 

Actual changes in performance were modest (Fig. 105). Alcohol levels of. 10% (10 mg%) were expected but, as with the above study by Sidell and Pless, actual levels reached this value in only 2 of 26 subjects. Mean blood level peaked at 0.07% at 1-2 hours. The officers indicated that they would have stopped 10% of placebo subjects, 32% of THC subjects, 50% of alcohol subjects and 60% of those with alcohol plus THC... 

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