One hundred forty-seven persons exposed to arsenic from well water were evaluated by neurologic examination and nerve conduction studies. Total arsenic concentrations in well water ranged from 1 to 4781 micrograms/L and from 6 to 4964 micrograms/L in urine; a calculated index of arsenic ingestion ranged from 1 to 4521 micrograms/day. No dose-response relationship existed between arsenic ingestion and symptoms or physical findings compatible with peripheral neuropathy. Five of six persons with symptoms or physical findings suggestive of sensory neuropathy had normal nerve conduction velocities. Thirteen persons with elevated arsenic ingestion but no signs or symptoms of neuropathy had one or more abnormal nerve conduction velocities. No dose-response relationship, however, existed between arsenic ingestion and nerve conduction velocities. The authors concluded that arsenic ingestion from well water at the concentrations found in this Alaskan community did not result in clinical or subclinical neuropathy.

Adult↗

PubMedDate not supplied

Bovine blood lead reference material.

A protocol is described for the preparation and characterization of bovine blood lead (Pb) reference material (RM). Adult bovine animals are orally dosed with Pb as Pb(NO3)2, and blood is collected directly from the jugular vein into 5-mL evacuated, low-Pb glass tubes containing EDTA as anticoagulant. The blood is cooled to 4 degrees C for 24 h and frozen and stored at -20 degrees C. Over 400 RMs were prepared and certified for reference values (RV) since the inception in 1974 of the Childhood Blood Lead Proficiency Testing Program. Five reference laboratories employing blood Pb methods of various principles were used to certify the RV, representing the true value, of 5 representative RMs containing 6.4-54.0 micrograms Pb/mL. Intertube homogeneity was verified by reference laboratories determining blood Pb in 20 tubes of 150 tubes collected from each of the 5 representative RMs. Intratube homogeneity was verified by an internal laboratory determining Pb in 12 consecutive 10-microL samples from 5 mL of blood in each of 3 representative RMs. Pb was unchanged in 37 bovine blood Pb RMs containing EDTA as anticoagulant after storage at -20 degrees C for 32-48 months.

Animals↗

PubMedDate not supplied

Bovine blood quality control material for cadmium, mercury, and lead.

A protocol is elaborated for the preparation and characterization of a quality control material (QCM) containing intrinsic concentration of cadmium (Cd) (0.8 microgram/L) and lead (Pb) (13.4 micrograms/dL) from bovine blood and an elevated QCM containing Cd (5.0 micrograms/L), mercury (Hg) (11.2 micrograms/L), and Pb (34.5 micrograms/dL) from bovine blood spiked with aqueous spiking-solutions prepared with salts of Cd, Hg, and Pb. Borosilicate glass septum vials of 7-mL capacity were filled with 5 mL of blood, sealed with Teflon-silicone discs and plastic screw caps, and stored at -20 degrees C. Quality control, intervial and intravial, and storage stability values for Cd, Hg, and Pb were ascertained by analyzing the blood in randomly selected vials by an internal laboratory using modified published methods which were established for detection limit, accuracy, and precision. Validation of the protocol was demonstrated by intravial and intervial homogenity for Cd, Hg, and Pb and no change occurred in the concentrations of the elements in bovine blood containing EDTA at storage temperatures of 4 degrees C and -20 degrees C for 2 years.

Animals↗

PubMedDate not supplied

Arsine evolution-electrothermal atomic absorption method for the determination of nanogram levels of total arsenic in urine and water.

An arsine evolution-electrothermal atomic absorption method is described for the determination of ng/mL concentrations of total arsenic in urine and water. Organic-arsenic compounds are decomposed with nitric, sulfuric, and perchloric acids. Sodium borohydride, a redesigned hydride generator, and an electric-heated absorption tube are used for arsine evolution and its conversion to atomic arsenic. The method has a detection limit of 6 ng/mL, a sensitivity of 1 ng/mL, and is linear from 0 to 110 ng/mL of arsenic. Accuracy was established with two different National Bureau of Standards Standard Reference materials, and mean errors from 0 to -2 were obtained.

Arsenic↗