Occupational Chemical Exposure Surveillance: Design and Validation of a Survey Rukmani Ramaprasad, MSc, MS Lisa Huguenin, PhD Paula Knudson, MS, CIH Eileen Senn, MS, CIH David Valiante, MS, CIH

2 Research Funding  This study on exposure surveillance methodology was funded by the National Cancer Institute through NIOSH’s National Occupational Research Agenda (NORA)  Three-year study began October 1999  Research staff include in-house research scientists and consultants on survey design, statistics, and scanning software

3 Occupational Chemical Exposure: Why Survey?  Timely & cost effective - Occupational exposure assessment through personal and/or area monitoring is costly and time consuming. Methods to estimate exposure for worker population in timely & cost effective manner are needed to prevent occupational chemical exposure.  Estimate exposure hazard - This research focuses on developing a survey to mail to employers to estimate exposure hazard or the potential for worker exposure.  Initiate primary prevention - The estimates derived from the survey could be used to engage in primary prevention activities at selected workplaces by mitigating or eliminating exposure.

4 Research Aims: Design and Validation of a Survey  Design survey to learn how targeted chemicals are handled at specific workplaces and characterize exposure hazard  Validate and audit survey responses  Develop scoring method to rank workplaces based on exposure hazard

5  Selection of chemicals six known or probable human carcinogens  Selection of industries Standard Industrial Classification (SIC) codes based on where the selected chemicals are likely to be handled Survey Design: Key Elements o cadmium o ethylene oxide o formaldehyde o lead o methylene chloride o crystalline free silica

6 Survey Design: Types of Industries/ Chemicals Targeted IndustryChemical(s) Targeted Primary metal, pigments, non-ferrous foundries Lead, cadmium Solvents, paint remover, rubber Methylene chloride Pottery, brick, tile, refractory, concrete, abrasives crystalline free silica Health care and surgical supplies Formaldehyde, ethylene oxide

7 Survey Design: Sample Selection  New Jersey workplaces that may use one of the targeted chemicals is identified from MarketPlace, a national database of businesses. Workplaces with one employee are excluded.  A stratified random sample of workplaces is selected using size of workforce as strata. Each workplace is selected for only one chemical. Final survey will be sent to 700 workplaces.  A random sample of respondents will be selected to audit and validate responses on-site

Survey Design: Key Survey Questions  Is the chemical handled?  What is the quantity of the chemical handled?  How is the chemical handled?  What are the patterns of handling?  How many workers handle the chemical?  What are their job titles and duties?  Are controls to reduce exposures in place? The survey questions address the three routes of exposure – inhalation, ingestion and dermal contact and exposure control mechanisms in place. 8

9 Chemical Exposure Surveillance: Research Methods  Develop & pre-test Chemical Survey design  Develop & pre-test on-site validation methods  Develop & pre-test scoring system  Mail final version of survey to 700 workplaces  Conduct on-site validation and audit of a sample of survey respondents  Score final version survey responses

Survey: Pre-tests  Evaluate survey design  Do employers understand the study’s objectives?  Are instructions and questions clear and easy to read?  Is the order of the questions logical?  Evaluate protocol  Are procedures practical and useful?  Can deadlines be met?  Evaluate employer cooperation  Do employers complete and return survey? Three rounds of pre-tests have been conducted to evaluate and improve the survey based on telephone follow up of respondents and non-respondents. 10

11 Pre-tests: Response Rates Pre-test Number of Workplaces SurveyedResponse Rate 1 st 3877% 2 nd 5044% 3 rd 11617% 4 th 80Pending

Survey: Key Revisions  Narrowed selection of chemicals  From original 34 carcinogens  To six – many OSHA 6B chemicals not in use  Changed source for identification of workplaces  From workplaces reporting chemical use in the New Jersey Right to Know database  To those in selected SIC codes from MarketPlace database  Changed “chemical use” questions  From: “Is chemical produced or used?” Answer - Yes or No  To: “How is lead typically handled at this worksite?” Answer - Yes or No to 17 statements 12

13 Survey: Key Revisions (cont’d )  Survey Packet - 1 st Pretest  2 cover letters, suggested steps, FAQs, 3 survey forms (37 questions total)  Survey Packet - 4 th Pretest  Brochure with Confidentiality Statement  Instruction sheet  Chemical Survey (39 questions)  Participant Form (12 questions)  Survey formatted for use with scanning software (Cardiff Teleform™)

14 What’s Next?  Pre-test on-site validation and audit methods  Select sample of 700 employers and conduct final survey  Select random sample of respondents and conduct on-site validation

15 Challenges Ahead  Survey  Survey is not mandatory  Must rely on employer cooperation  Can’t offer financial incentives  Balance number of questions vs.employers’ time  On-site validation  Gain employers’ cooperation for on-site visit  Finalize method to determine validity of responses