| Specimen requirement | Spot urine (if
suspected acute poisoning): Special acid wash bottle for trace elements Volume: 10 mL 24 Hr urine (if suspected chronic poisoning): U6 bottle |
| Authorisation code required | Yes |
| 24 Hr available service | No |
| Precaution | Seafood must be excluded from the diet for seven days, as they may contain high levels of non-toxic organic arsenicals. |
| Method | Inductively coupled plasma-mass spectrometry (ICP-MS) |
| Reference interval |
Urine:
< 90 nmol/mmol Cr
< 670 nmol/d
(Source: Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 5th Edition. 2012) |
| Clinical indication | Suspected arsenic poisoning. |
| Result interpretation |
Arsenic is mainly measured to assess occupational exposure: e.g. workers manufacturing semiconductors in the microelectronics industry; agricultural workers using a variety of arsenical herbicides and pesticides; workers exposed to wood preservatives containing copper, chromium, and arsenic. Exposure can be monitored by measuring urinary excretion of arsenic, which is present as arsenite [As(III)], arsenate [As(V)], their metabolites methylarsonic acid and dimethylarsinic acid and the more stable forms, arsenobetaine and arsenocholine. The latter two forms are non-toxic and are present in the normal diet especially in fish. |
| Measurement of uncertainty | See table. |
| Frequency of measurement | Weekly |