Autoantibody responses of individuals in an oil sands development community

ENVIRONMENTAL AGENTS of that kind as mercury (1) and pristine (2) have been shown to induce autoimmunity in susceptible animal prototypes Organic solvents, (3,4) mercury, (5) vinyl chloride, (6) and silica (7) are among the agents described to induce or accelerate autoimmunity in humans. The Athabasca Oil Sands, near Fort McMurray in northern Alberta, Canada, exhibits one of the largest in a raw state petroleum reserves in the world. The undressed petroleum is heat-extracted from a mixture of bitumen, sand, water, and clay in an open-pit mining operation. (8) Community be of importance tos about air quality and health readyed the Government of Alberta, with industry partners, to undertake a multidisciplinary assessment of exposing and health outcomes. (9) Potential in all senses risks included sulfur dioxide, nitrogen dioxide, ozone volatile organic blends and particulates such as heavy metals. In view of the link between a certain number of of these environmental agents and autoimmunity, we studied the nearness of autoimmune disease and serological markers of autoimmunity in proffer residents adjacent to this industry.

Method

Recruitment of subdues We recruited volunteers aged 18 and above through local media and phone solicitation from major employer in the oil sands industry. subdues had to reside in the application of mind community of Fort McMurray or the superintendence community of Lethbridge (where there is no oil sands unravelling 968 km [601 miles] south) the couple in the province of Alberta, Canada. We obtained written informed approval from all participants.

Questionnaires and health consequences We used questionnaires regarding occupational and home-related exposing s (9-11) physical limitations, (12) and previous diagnoses. We reviewed International Classification of Diseases (ICD 9) diagnostic digests (13) for physician visits from January 1992 to December 1998 and for hospitalizations from April 1992 to March 1998 for the vicinity of autoimmune and systemic rheumatic diseases. We included the ICD 9 collection of lawss 695.4; 710; 711; 274; 696; 714; 7164; 7165; 720; and 725 in this analysis.

Autoantibodies. Initial testing for immunoglobulin G (IgG) autoantibodies used indirect immunofluorescence (IIF) microscopy using commercially available HEp-2 confined apartment substrates (HEp-2000[TM] ImmunoConcepts, Sacramento, CA) at a screening dilution of 1:160 We considered the proof positive when we detected a fluorescence intensity of 1 + (IIF staining pattern clearly visible) or greater at a serum dilution of at least 1:160 (14) We finded antibodies to double-stranded DNA (dsDNA) by the agency of using the lie method upon Crithidia luciliae substrate (ImmunoConcepts), and we considered the experiments positive when all of the kinetoplast was stained at serum dilutions of 1:20 The Luminex 100[TM] addressable laser bead combination of parts to form a whole (Luminex, Austin, TX) uses places of beads that have incorporated different fluorescent coloring liquors We used the QUANTA Plex[TM] Profile 9 (INOVA Diagnostics, San Diego, CA) to experiment IIF-positive sera for autoantibodies to Smith (Sm); ribonucleoprotein (U1-RNP); SS-A/Ro; SS-B/La; topoisomerase I (Scl-70); histidyl tRNA synthetase (Jo-1); ribosomal P proteins; and chromatin. (15)

BTEX intermixs We quantified mandelic acid; hippuric acid; and the isomers 2- 3- and 4-methylhippuric acid in urine as metabolites of benzene, toluene, ethylbenzene, and xylene (BTEX) respectively, using liquid chromatography. We measured muconic acid in the urine through gas chromatography and mass spectrometry to assess exposing to benzene. Details of these rules were described previously. (9)

Statistical analysis. We performed statistical analysis with SPS Base 100 (SPS Inc., Chicago, IL) software. We compared frequencies with the chi-square or Fisher's exact ordeals We compared age distributions with the Mann-Whitney experiment and made adjustments for the potential confounder of age and sex We examined relationships between occupational exposing s and autoantibody result with unevens ratios. We examined BTEX biomarker horizontals for a relationship with autoantibody issue by (a) scatter plots, (b) logistic regression with autoantibody proceed as a dichotomous outcome, and (c) horizontal comparison using the Mann-Whitney test

Results

We obtained a total of 244 serum samples, 214 from the research group and 30 from directions The groups were comparable in age (mean ages = 393 and 442 in research and control groups, respectively) and sex distribution (ratio of women to men = 1:1 in each group) Thirteen percent of the research participants had a positive IIF screening trial for autoantibodies, versus 10% of the superintendences (p > 0.05). Of interest, the close attention group had higher titers of autoantibodies, with 9 at 1:160 6 at 1:320 8 at 1:640 3 at 1:1280 and 1 at 1:5120 whereas all three positives in the sway group had titers of 1:160 which is the lowest dilution that defines a positive trial (14)

Specificity testing revealed that 05% were powerfully positive for anti-SS-A; 0.5% powerfully positive for anti-Sm, U1-RNP, and antichromatin; and 1% weakly positive for antibodies to Scl-70 We set none of these autoantibodies in the rule sera. We found antibodies to dsDNA in 05% of the application of mind participants and 3% of the masterys Antichromatin antibodies were present in an additional 3% of the close attention group and 10% of the ascendencys with all but one of these being weakly positive.