Transcript Environmental Regulations and Possible Roles for OHs

Environmental Regulations
and Possible Roles for OHs
A presentation by
Brett Ibbotson
to the
Occupational Hygiene Association of Ontario
March 2007
There are increasing opportunities in Ontario for
OHs to participate in the human health risk
assessments required by regulations.
In other words,
there is more (and different) work for OHs
(if you want it).
In the Beginning…
• People are adept at weighing the risks and
benefits of their daily activities.
• In the vast majority of cases, this is done
spontaneously and on a more or less continuous
basis.
The Evolution of RA
• Around 150 years ago, record keeping improves
at hospitals, insurance companies, and
government agencies.
• As information accumulates, it becomes possible
to predict the rates of certain outcomes such a
life expectancy.
• In the 1940s and 1950s, with the first attempts
at harness nuclear energy, it became possible to
measure tiny exposures to radioactive materials
and to understand the relationship between
exposure and health effects.
• By the 1960s, lessons learned by nuclear
scientists start to be applied to exposures to
non-radioactive substances and chemicals.
• Some methods predict health effects based upon
statistics from past exposures (epidemiology).
• Other methods predict effects based upon lab
studies the dose-to-response relationship
(toxicology).
OH and RA – Same but Different
At a basic level, the OH and the RA share a
common objective – identify possible unwanted
outcomes and take steps to reduce those to
“acceptable” frequencies.
On many other levels, the two occupations are
distinctly different.
• There have been OH regulations in Ontario for
more than 100 years; Ontario Factories Act
passed in 1884
• RA was not considered in Ontario environmental
regulations until the 1980s; maximum
acceptable concentrations for PCBs in soil set in
1987
• OH most often deals with healthy adult workers
who are exposed for 8 h/d, 40 h/w, 50 w/y
• RA considers people of all ages, and sensitive
subpopulations such as seniors. Exposures can
be continuous, for years, even a lifetime. Also
considers ecological receptors.
• OH addresses a wide spectrum of hazards that
include machinery, chemicals, energy, noise and
vibration, physical hazards, ergonomics, etc.
• RA in Ontario mostly used to address chemicals
in the environment
Defining “Acceptable” Risk
• To manage risks, “acceptable” risk needs to be
defined.
• How this is done appears to be an obvious point
of divergence between the two disciplines.
• One cause is the human receptors each
considers (healthy adults in the workplace vs the
general population).
In the RA World
• This key point continues to evolve and some
agencies have revised definitions occasionally.
• Common definitions in Ontario:
– 1 x 10-6 for non-threshold toxicants
– hazard quotient of not more than 0.2 for
threshold toxicants
Occupational limits from MOL often seem fairly liberal
relative to environmental limits set by MOE.
Chemical
MOL TWAEV
MOE AAQC
acetone
1,200
11.8
copper
0.2 to 1
0.05
methylene chloride
175
0.044
naphthalene
52
0.023
perchloroethylene
170
0.36
All in mg/m3
• Despite challenges such as the need to define
acceptable risk and what to do when
“background” concentrations exceed acceptable
risk levels, RA became a regular component of
environmental management in Ontario during
the 1990s.
RA Since 2000
In 2001, a major review of how the MOE works
(the Gibbons report):
• acknowledged that RA is a primary tool for
setting environmental standards
• concluded that the process could be improved
by developing a new approach which it called
“risk analysis” that encompasses RA, RM, and
risk communication
It identified aspects of the RA approach used by the MOE
that need to be improved:
• Little attention is paid to other disciplines including
sociology, economics, law, and health sciences.
• Does not deal effectively with multimedia,
multichemicals, and examines sites based on artificial
boundaries such as legal descriptions rather than
“naturally” defined areas (like a watershed).
• Public consultation is limited to back end discussions of
implementing decisions rather than up front in priority
setting.
O. Reg. 153/04
• Record of Site Condition Regulation
(sometimes called the Brownfields regulation)
• Presents generic standards for chemicals in soil,
ground water, and sediment.
• Also gives property owners the option of using
RA to recommend property-specific standards.
The RA Option in O. Reg. 153/04
• Begins by identifying the types of human and
ecological receptors that could come into contact
with the contaminants of concern.
• Then determines which exposure pathways
could be complete.
Conceptual Site Model (CSM)
COMPONENT APPROACH
INDOOR AIR
ECOTOXICITY
HUMAN HEALTH
DIRECT CONTACT
S-1, S-2, S-3
MAMMALS AND
BIRDS
GROUNDWATER
INGESTION
Soil Vapour VM1
VM2
Contaminated Soil
AQUIFER
Groundwater Vapour
AQUATIC
TOXICITY
• For each potentially complete combination of
receptor chemical and pathway, either measure
or estimate (using mathematical models) the
concentrations the receptor will encounter.
• Calculate average daily exposures and doses by
combining those concentrations with receptor
characteristics (i.e. body weight, inhalation and
ingestion rates, etc.) and behavioral
characteristics to determine frequency and
duration of exposure.
• Select toxicity reference values (TRVs) for each
chemical (i.e. reference doses or concentrations,
inhalation unit rates, slope factors, etc.)
• Most TRVs come from published sources (MOE,
Health Canada, the U.S. EPA, WHO, etc.)
• Use the TRVs to estimate potential risks posed
by the estimated exposures and doses.
• Repeat the calculations in reverse, starting with
the acceptable risk levels (i.e. 1 x 10-6 or a HQ
of ≤ 0.2) to calculate the corresponding
maximum acceptable concentrations.
• Those maximum acceptable concentrations
become the property specific standards.
• If property specific standards are exceeded,
either remediate or install risk management
measures.
Qualified Person in Risk Assessment
O. Reg. 153/04 requires that an RA be prepared by a team
led by a qualified person in risk assessment (QPRA) who
has the following qualifications:
Degree
Experience
in ESA or RA
Experience
in RA
Bachelors in science, engineering, or
applied technology
8 years
2 years
Masters in science or engineering
7 years
2 years
Doctorate in science or engineering
5 years
2 years
The RA Team
Expected to have various “key team members”, which as a
minimum, need to address the following areas:
• Human health toxicity*
• Ecotoxicity*
• Hydrogeology*
• Soil science or chemistry
• Environmental science or chemistry
• Analytical chemistry
• Engineering
O. Reg. 419/05
• principal air quality regulation in Ontario
• sets standards for many chemicals in outdoor air
• many of the generic standards have been set to
ensure that risk levels not exceed 1 x 10-6 or
HQs of 1
• Includes a schedule of dates when various categories of
emitters are to comply with the standards.
• Emitters not able to meet generic standards by the
prescribed dates can set “alternative standards” and
embark upon a program of continuous improvement until
generic standards are met.
• The Guideline for the Implementation of Air Standards in
Ontario or GIASO describes the procedure.
• Like the RSC Regulation, GIASO describes the
alternative standard procedure in considerable
detail.
• The assessor identifies the locations of the
human receptors to be evaluated.
• Prescribed air dispersion models are used to
estimate concentrations at each receptor
location.
• “Risk scores” are calculated based on factors
such as how frequently a standard is exceeded
and weighting factors that are based on the
types of adverse health effects a chemical can
cause.
• Risk scores are combined to help choose control
options.
• Unlike the RSC regulation, there is nothing
analogous to the QP. In fact, there is no
description of who can develop alternative
standards.
• There is a potential role for a toxicologist or OH
to work with an air dispersion modeler to
establish the risk scores.
Conclusions
• Increasingly, in Ontario, environmental policies
and regulations are advocating decisions based
on managing human health and ecological risks.
• There are various scenarios where property
owners, facility operators, and consultants can
prepared human health RAs.
• There is a growing expectation that these
assessments be prepared by RA teams.
Conclusions
There are increasing opportunities in Ontario for
OHs to participate on the HHRAs required by
regulations.
In other words, there is more (and different) work
for OHs (if you want it).
Some Important Statistics
• By 2017, 50% of all the senior managers,
directors, and supervisors currently in the
Canadian workforce will have retired.
• For each two people who retire, there will be
less than one new person entering the
workforce.
• At the same time, the amount of RA and RM to
be done will continue to increase.
What Could This Mean?
• Increasing pressure to work beyond 65.
• Increasing pressure for baby boomers to take on
mentoring roles. Current university and college
curricula pay little attention to RA. It is a skill
largely learned by participating.
• With more RA work to be done, and toxicologists
already in short supply, OHs will be sought out
to assist with HHRAs.
The Real Conclusion?
There is more (and different) work for OHs.
It may coming looking for you even if you don’t go
looking for it.