Chemistry is not a “Zero Exposure” Occupation

Harry J. Elston, Ph.D., CIHMidwest Chemical Safety, LLCDawson, IL

“Chemistry is not a zero-exposure occupation. You are not entitled to zero exposure. You are entitled that your exposure be kept below recognized occupational exposure limits and to be informed of the hazardous properties of the materials with which you work.”

Producers and Consumers Colleges and Universities are

manufacturers of a product Who are the consumers? Industry – Research, QA/QC, etc. Government – Environmental,

Transportation, Law Enforcement… Academia – graduate and professional

schools

What the Consumer Wants on Day 1:

Basic chemical calculations Basic chemical manipulations

(dilutions, distillations, prepare solutions, etc.)

Has basic understanding of hazard (acids/bases are corrosive, cyanides are toxic…)

Day 1: Basic understanding of safe waste

management (don’t mix organics with nitric acid, waste segregation, etc.)

Basic understanding (and respect) forrisk management Can put the risk equation together:

Risk = hazard x P(exposure) Has respect for chemical hazards, but

not fear

A completely unscientific survey for this presentation Reviewed GenChem and Organic Chem

textbooks and lab manuals from 4 undergrad institutions

What I consider are problems: Lab manuals never had the student make dilutions

from concentrated stock acids/bases Labs have removed use of toxic material for

separations (CS2, carbon tetrachloride, dichloromethane, cyanides in qual schemes, etc.)

Reasons for chemical substitution are not explained

PPE is prescribed but not explained. No risk assessment is performed.

No hazard assessments or risk evaluations shown

Missing teachable moments Dilutions and chemical manipulations Understanding risk information MSDS/SDS (a starting place) Interpreting MSDS/SDS in light of

concentration Other toxicology information Interpreting conflicting tox data

Safely working with hazardous/highly hazardous material (like they will when they graduate)

Leading from the front (of the classroom or lab)

Introducing “hazard” to students In “pre-lab” exercises: “Hazard” is an inherent property of the

chemical “Hazard” is reduced by dilution Talk about choice of chemicals used

In the classroom Introduce industrial chemical use

Leading from the front Risk and Risk Management What is risk? Risk (consequence) = Hazard x P(exposure) Balance hazard/exposure to keep risk

acceptable Introduce to the student the “whys” Chemical substitution (hazard) SOP/PPE (exposure) Risk assessment tools at higher levels

Leading from the front In the lab Handling hazardous chemicals/waste

safely Keep risk perspective – make it part of

the pedagogy Make working safely part of the

evaluation Reward those who work safely, penalize

those who are demonstratively unsafe