A report was presented of a capillary gas chromatographic method developed for quantitating mandelic-acid (90642) (MA) and phenylglyoxylic-acid (611734) (PGA), urinary metabolites of styrene (100425). Urine samples with added internal standard were treated with sulfuric-acid and zinc to reduce PGA to MA. Ethyl-acetate extracts were prepared and treated with N,O-bis-(trimethylsilyl)- trifluoroacetamide and isooctane prior to capillary gas chromatography with flame ionization detection. The method was calibrated using urine from an unexposed individual, containing internal standard only or spiked with MA to yield final concentrations of 0.001 to 2mg/ml. Urine samples were obtained from workers at three reinforced fiberglass products facilities (truck manufacturing, plastic pipe and tank manufacturing, plastic grate manufacturing). Replicate analyses of workers' urine samples initially showed large variation, due to poor solubility in derivatization solution of residue from solvent evaporation. Tests of several solvents indicated that dry ethyl-acetate gave the best response, providing the lowest coefficient of variation and reducing the lower limit of quantitation to 0.01mg/ml. Detector linearity and column loading limitations provided an upper limit of 2 to 4mg/ml. The lower limit (about 0.001mg/ml) was below typical MA levels in urine of unexposed persons. Spiked urine sample analysis yielded linear standard curves, with slight differences in slopes for MA and PGA. Relative precision below 5% was obtained in the range 0.05 to 2mg/ml. PGA was quantitated by the difference between MA measured with and without reduction. The authors conclude that this method provides increased precision and sensitivity for assay of urinary MA and PGA.
Links with this icon indicate that you are leaving the CDC website.
The Centers for Disease Control and Prevention (CDC) cannot attest to the accuracy of a non-federal website.
Linking to a non-federal website does not constitute an endorsement by CDC or any of its employees of the sponsors or the information and products presented on the website.
You will be subject to the destination website's privacy policy when you follow the link.
CDC is not responsible for Section 508 compliance (accessibility) on other federal or private website.
For more information on CDC's web notification policies, see Website Disclaimers.
CDC.gov Privacy Settings
We take your privacy seriously. You can review and change the way we collect information below.
These cookies allow us to count visits and traffic sources so we can measure and improve the performance of our site. They help us to know which pages are the most and least popular and see how visitors move around the site. All information these cookies collect is aggregated and therefore anonymous. If you do not allow these cookies we will not know when you have visited our site, and will not be able to monitor its performance.
Cookies used to make website functionality more relevant to you. These cookies perform functions like remembering presentation options or choices and, in some cases, delivery of web content that based on self-identified area of interests.
Cookies used to track the effectiveness of CDC public health campaigns through clickthrough data.
Cookies used to enable you to share pages and content that you find interesting on CDC.gov through third party social networking and other websites. These cookies may also be used for advertising purposes by these third parties.
Thank you for taking the time to confirm your preferences. If you need to go back and make any changes, you can always do so by going to our Privacy Policy page.