Urinary biomarkers early effects

Because hexachlorobenzene can interfere with porphyrin metabolism and produce chemical porphyria, the evaluation of the urinary porphyrin pattern has been proposed as an early biomarker of effect (San Martin et al., 1977 Schmid, I960, 1966 Wray et al., 1962). However, apart from an outbreak of chemical porphyria which occurred in Turkey in the 1950s following ingestion of hexachlorobenzene-contaminated food, cases of chemical porphyria among... 

Price RG, Taylor SA, Chivers I et al. (1996) Development and validation of new screening tests for nephrotoxic effects. Hum Exper Toxicol 15 S10-S19 Price RG, Berndt WO, Finn WF et al. (1997) Urinary biomarkers to detect significant effects of environmental and occupational exposure to nephrotoxins, III. Minimal battery of tests to assess subclinical nephrotoxicity for epidemiological studies based on current knowledge 19 535-552 Price RG (2000) Urinalysis to exclude and monitor nephrotoxicity. Clin Chim Acta 297 173-182 Price RG (2002) Early markers of nephrotoxicity. Comp Clin Pathol 11 2-7... 

The more recent literature on the relationship of Pb-B, 6-ALAD genotype, various other markers of Pb exposures, and various toxic endpoints is a complex, seemingly inconsistent body of information across the various studies and some of the information appears anomalous (Table 16.5). Some issues of concern are the relationship of isozyme genotype to general indicators of exposure intensity such as employment duration and intensity, other biomarkers of Pb exposure such as patellar or tibial bone Pb levels, and biomarkers of early effect such as ZPP, plasma ALA, urinary ALA, and clinical markers of effect such as those for renal function. 

A recent review on arsenic biomarkers concluded tiiat urinary and toenail biomarkers are convenient indicators of internal arsenic dose while the MN assay may be complementary biomarker of early effects. Authors also highlighted the limitations and advantages of biomarkers [30 ]. 

Fortunately, urinary bladder cancer is amendable to effective treatment if detected early. A full spectrum of biomarkers and early diagnostic screens are available to alert the health professional when exposure to 2NA has occurred and when changes consistent with early neoplasia are occurring. 

Arsenic-induced oxidative stress is well established and is known to play important role in onset or progression of various pathological manifestations. Various oxidative stress-related markers may not prove to be specific biomarkers in arsenic toxicity but they may contribute as important parameters to diagnose early signs of arsenic-induced adverse effects [23 ]. A study with 157 participants in China demonstrated a positive correlation between the levels of serum thioredoxinl and the total water arsenic intake or the levels of urinary arsenic species. Authors suggested that since changes in human serum thioredoxinl can be detected before arsenic-specific dermatological symptoms, it may serve as an early biomarker for the same [24 ]. 

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