Final Flashcards
type 1 error
falsely assuming the mine is having a detrimental effect - causing unnecessary costs
type 2 error
falsely assuming the mine is having no detrimental effects, causing environmental damage
who is the CCME composed of and what guidelines do they make
the canadian council of ministers of the environment
composed of one minister of the environment from each province and territory, and one federal minister
responsible for addressing major environmental issues, and making the Canadian environmental quality guidelines
what five media do the Canadian environmental quality guidelines cover
water
air
soil
tissue
sediment
difference between the guidelines, objectives, and standards for water quality
guidelines are numerical concentrations or narrative statements recommended for a specific water use
objectives are numerical concentrations or narrative statements that have been established to support and protect the designated uses of water at a specific site
water quality standards are objectives (as defined above) that are recognized by enforceable environmental control laws in a level of government
what are the two values listed for most Canadian water quality variable guidelines
short term exposure guidelines - designed to protect a specified fraction of individuals from severe adverse effects (ex: lethality) for a defined short-term exposure period - DO NOT fulfill the guiding principle of protecting all components of the aquatic ecosystem at all times
Long-term exposure guidelines - meant to protect against all negative effects during indefinite exposure
ECx (MMDME)
effective concentration - the concentration of material in a media that is estimated to cause a specified toxic effect (either it happens or it doesn’t) in x% of test organisms
ICx
inhibiting concentration - point estimate of a concentration of test material that is estimated to cause a designated percent impairment in a quantitative biological function
what is the next lower concentration from the LOEC
the no observed effect concentration
MATC (MMDME) what is it and where does its true value lie
maximum acceptable toxicant concentration - true value should lie somewhere between the NOEC and the LOEC
describe the difference in when you would use a Type A and Type B guidelines for Canadian environmental quality guidelines (MDMER)
Type A guidelines - derived using a species sensitivity distribution (SSD) approach with adequate primary and secondary toxicity data to make a good fit on an SSD curve
Type B guidelines - data is inadequate or insufficient for a proper SSD approach, but there is enough from a minimum number of primary (B1) or secondary (B2) studies to extrapolate from the lowest available and acceptable toxicity endpoint
what is the preferred end point of a type A guideline for the Canadian environmental quality guideline
no effect threshold (ECx/ICx)
what is the preferred end point of a type B guideline for the Canadian environmental quality guideline
a low effects threshold for the most sensitive species (ECx/ICx)
which organisms are required in the data set when developing a Type A and B1 Canadian environmental (water) quality guideline
Fish: at least three freshwater species resident in North America, including at least one salmonid and one non-salmonid
Invertebrates: at least three aquatic or semi-aquatic invertebrates, at least one of which includes a planktonic crustacean
Plants - at least one study of a freshwater vascular plant OR a freshwater algal species. If the target variable of interest is highly variable - you need three studies
primary data for canadian environmental (water) guidelines (MDMER)
toxicity tests that employ currently acceptable lab practices of exposure and environmental controls. at a minimum, the toxicant concentrations must be measured at the beginning and end of the exposure period
how are Type B Guidelines derived
from the Lowest observed effect concentration of a CHRONIC study of a nonlethal end point for the most sensitive aquatic species being investigated
data requirements should be primary data
the LOEC derived should be multiplied by a safety factor of 0.1 to account for interspecies differences, lab vs field conditions, etc
how are type A guidelines derived (describe the graph)
using a Species sensitivity distribution:
the log concentration of the substance of interest is on x axis, and the cumulative percentage of species affected on the Y axis.
shape of graph is usually sigmoidal or S shaped
The guideline (which may be the short term exposure or a long term exposure concentration guideline, depending on the data you are analyzing) is typically set as the fifth percentile, representing the concentration at which five percent of the species are negatively affected by the substance of interest
if you are using an SSD graph to determine the no effect level what must you do
if yo pick the concentration at the %5 level - NO species must be affected at the 5% conc
what is sediment
particles derived from rocks or biological materials that are stationary in the bottom of a water course. sediment is a habitat for many organisms, plays a role in nutrient recycling, and can accumulate and re-release contaminents i
ideally, sediment quality guidelines should be developed rfom
concentration-response curves which describe the acute and chronic toxicity of individual chemicals in sediments to sensitive life stages of sensitive species
what are sediment quality guidelines
numerical concentrations or narrative statements intended to protect all forms of aquatic life and all aspects of their aquatic life cycles during an indefinite period of exposure to substances associated with bad sediments
what two measurements can be used to evaluate the degree to which adverse biological effects are likely to occur due to exposure to a substance in sediment
interim sediment quality guidelines (ISQGs) and probable effect levels (PELs)
sediments that have concentrations below the interim sediment quality guidelines (ISQG) are
unlikely to have adverse biological effect
ISQGs and PELs refer to
total concentrations in surficial sediments (within the first five centimetres) as quantified by digestion with a strong acid
metal content in sediment is a natural function of
particle size distribution
define ecological risk assessment (Doig’s lectures)
a process for estimating the likelihood of adverse ecological effects as a result of exposure to stressors related to human activities
what is ecological risk assessment used for (DOIG)
organizing information and contributing to informed decision making
ex - determining which species at a site are at risk, identify critical knowledge gaps
two conditions for a chemical to pose risk in the environment
1) chemical must have an inherent ability to cause some undesirable or hazardous ecological effect
2) chemical must be present in the environment at sufficient concentrations to cause adverse effects in the organism (receptor)
assessment endpoints vs measurement endpoints
assessment endpoints describe what you are trying to protect (fish, ecosystem) whereas measurement endpoints describe what you are actually going to measure (population abundance, reproduction)
what is the effect characterization part of the ecological risk assessment
defining the spatial and temporal distribution of the stressor and the ecological component being measured - looking at the co-occurrence of the stressor and the biological endpoint
evaluates the toxicity or hazard of the stressor to biota
what is a conceptual model
basically a picture depicting the interaction between a stressor and the ecosystem in which it is found
risk characterization estimates the probability that some adverse effect may occur as a result of exposure to a stressor by
using the quotient method:
estimated environmental conc (EEC) / toxicological benchmark conc (threshold for a particular tox endpoint)
if quotient is greater than 1 - increased risk of effect occurring
the fisheries act of 1868 prevents
the deposit of deleterious substances into waters frequented by fish UNLESS authorized
define deleterious substance by the fisheries act
any substance that if added to any water would degrade/alter/or contribute to a process to degrade/alter the quality of the water such that would likely be rendered deleterious to fish or fish habitat, or to the use by man of fish
or
any water that contains a substance in such quantity or concentration that has been treat, processed, or changed by heat or other means from its natural state such that if added to any other water it would degrade or alter or form part of a process of degradation or alteration of the quality of the water so that it is rendered or is likely to be rendered deleterious to fish or fish habitat or to the use by man of fish
what does MDMER stand for
metal and diamond mining effluent regulations
under what act does the MDMER fall
the fisheries act
what is the objective of the MDMER
to LIMIT the deposit of deleterious substances into waters frequented by fish from new, expanded, and reopened mines and diamond mines
the MDMER applies to
all meal or diamond mines in Canada that have effluent discharge exceeding 50 cubic metres per day and discharge a deleterious substance
final discharge point
an identifiable discharge point of a mine beyond which the operator of the mine no longer exercises control over the quality of the effluent - THERE MAY be more than one
tailings
the materials left over after the process of separating the valuable fraction from the uneconomic fraction of an ore
overburden
the waste rock or other material that overlies an ore or mineral body and is displaced during mining without being processed
when is a mine authorized to deposit effluent in water
1) if the conc does not exceed maximum authorized conc
2) the pH of the effluent is 6-9.5
3) not acutely lethal
MDMER sets effluent concentration limits for the following substances
metals (arsenic, copper)
cyanide
un-ionized ammonia
total suspended solids TSS
a defined range for pH
radiation from radium-226
mines are required to do acute toxicity testing for these species
rainbow trout for 96h and daphnia magna for 48h
if the effluent is very salty than also do threespine stickleback (96h) and acartia tonsa (48h)
what is the EEM and what is its purpose
environmental effects monitoring program - to evaluate the effects of mine effluent on fish, fish habitat, and the use of fisheries resources in order to refine the MDMER authorized effluent list and concentration limits (addresses uncertainty)
what three types of studies does the EEM require mines to perform
effluent quality monitoring studies - effluent characterization (concentration of additional compounds in the effluent), and sublethal toxicity testing (detect potential long term effects)
water quality monitoring studies - water quality monitoring in the receiving environment, beyond the final point of discharge
biological monitoring studies - fish population health studies, fish tissue studies, benthic invertebrate community surveys
what type of specimens must mines do sublethal toxicity testing on for the EEM effluent quality monitoring studies
freshwater environment - a fish, invertebrate, algal species, and a plant
marine - fish, invertebrate, algal species
how long does a mine have before it must submit a study design for a biological monitoring study
12 months
mines should report what two qualities of the sediment collected for benthic invertebrate community surveys
organic carbon content and particle size distrubution
if a mine cannot do a fish survey, they should do
mesocosm studies (artificial stream systems)
caged bivalve studies
expanded sublethal toxicity testing
if a mine cannot do a benthic community survey, the recommended alternative is
a mesocosm study (a study that simulates the environmental conditions - artificial stream study)
what are the three categories of biological monitoring studies
initial monitoring (for when there are no previous studies/available data) - determine if the effluent is causing an effect
focused monitoring studies - determine the magnitude and geographical extent of the effect
investigation of cause monitoring studies - for if the cause is still unknown
occupational medicine
branch of medicine dealing with the effects of the work environment on health and the effects of ill health on the ability to work
management of occupational illness and injury and promotion of health and productivity
environmental medicine
branch of medicine devoted to prevention/management of adverse health outcomes from exposure to chemical or physical agents in ones environment/community/home
what was ramazzini’s big teaching for occupational medicine
visit a patients workplace to learn about hazards
ask what is your trade
in assessing exposure (occ med) what three things should you do
ask - what do they do, how do they do it, what exposures may occur - MSDS
observe - site visit and walk through
measure - exposure levels, dose, area and personal monitoring, biological monitoring like medical screening
what three points are on the disease model triangle of illness for occ med
host
agent
environment
what are the different types of hazards a person may be exposed to in the workplace
physical (different sources of energy - noise, vibration, temp)
chemical/particulate (gases, dusts, mist)
biological (bacteria, fungi, viruses)
ergonomic
psychological
case of the 37 year old male who worked in aircraft maintenance complained of headaches, dizziness, sluggish - relate to work - what was the cause
inhalation of jet fuel
what are occupational exposure limits referred to in sask
contamination limits (CLs)
many jurisdictions determine their occupational exposure limits (OELs) based on
the threshold limit values outlined by the American conference of governmental industrial hygienists
TLVs refer to -
airborne concentrations of substances and represent conditions under which it is believed that NEARLY all workers may be repeatedly exposed day after day, over a working lifetime, without adverse health effects
TLVs are developed to protect
workers who are normal, HEALTHY, adults
what are TLVs intended to be used for vs not intended to be used for
they are intended for use only as guidelines or recommendations to assist in hazard evaluation and control
they are not for use in community air pollution, extended work periods (where the worker is there for over eight hours), or proving/disproving disease in an individual
**they are not fine lines between safe and dangerous
what are the three types of TLVs
TWA - time-weighted average (8hr work day, 40 hrs a week which nearly all workers may be repeatedly exposed to for a life time without adverse effect)
STEL - short-term exposure limit - 15-minute avg exposure that should not be exceeded at any time during a workday
C - ceiling - conc that should not be exceeded during any part of working exposure
what are excursions in regards to TWA
concentrations of a hazard that a worker could be exposed to over 3X the TWA for no more than 30 minutes per workday, and cannot exceed 5X the TWA
only applies to substances that have no STEL
how are dusts/particulates/fumes measured
collected on a filter and weighed
chemicals, solvents, and vapours are measured how
collected in liquid or granular sorbent media (charcoal, silica)
legal occupational exposure limits are based on (personal or area) limits
personal monitoring limits
industrial hygiene
the science and art devoted to anticipation, recognition, evaluation, and control of environmental factors or stresses arising from the workplace
what is the hierarchy of controls in occ med
eliminate or substitute one hazard with a non-hazardous or less hazardous one
engineering controls (enclosures, pipes, soundproofing)
administrative controls (rotate workers)
personal protective equipment (last line of defense
which form of government (provincial, federal, municipal) is responsible for health and safety laws
provincial
in sask - ministry of labour relations and workplace safety
sask was the first jurisdiction in canada to legislate …
making health and safety the joint responsibility of management and workers
requiring joint worker-management committees to actively identify and resolve health and safety issues
enshrine and protect workers’ fundamental rights
what are the fundamental rights of workers in Sask
to know about hazards, how to identify them/protect themselves
to participate in health and safety decisions
to refuse unusually dangerous work
two pieces of legislature that govern workplaces under provincial jurisdiction in sask
the Saskatchewan Employment act
the occupational health and safety regulations
act vs regulations
act = what must be done
regulations = how it must be done
three ways to check for lead in occ health case study
air sampling for lead particulate
surface samples (wipe the surface, note if color changes)
bio monitoring - blood lead levels
for the rocky mountain arsenal case study - what two monumental decisions were made in 1995
the off-post record of decision (ROD) and the on-post ROD which provide the framework, purpose, and rationale for clean-up actions
what was the dioxin issue with the rocky mountain arsenal case study
previous work for remediation was only based on organochlorine pesticide residues, but during the remedial action phase in the late 1990s, it became apparent that dioxins were present on site
two objectives of the dioxin issue
to determine conc of TCDD-equivalents (dioxins) in the wildlife of the RMA and compare these concentrations to those in surrounding reference areas
to determine the risk associated with exposure to dioxin like compounds in these areas
how was risk assesed in the RMA case study
TCDD-EQ conc in tissue samples / TRV (toxicity reference values) = HQ
if HQ over 1, increased risk
TCDD-EQ and TEQ in RMA case study
TCDD-Eq = bioassay of mammalian cells to detect the presence/toxicity of chemicals (indirect measure of tox)
TEQ - instrumental measurements of the concentration of chemicals multiplied by a toxicity factor - only looking at known contaminants
results of the RMA case study
american kestrel eggs - TCDD-EQ and TEQ conc were comparably low, if anything lower on RMA site - HQ<1
great horned owl livers - TEQ and TCDD-EQ results comparable but there was statistically significant differences in the TCDD-EQ between adult owls from reference and RMA
overall there were some significant differences in TCDD-equivalent conc between reference sites and RMA locations, indicating a possible point source of dioxin contamination - but there were small sample sizes and no sig differences in TCDD-eq in kestrels
aquatic systems likely not at risk - low HQ in carp
future indications for RMA case study
the scientific opinion that the pCDD/Fs were not a contaminant of concern and any source of contamination would likely be removed by ongoing remediation activities - but the evaluation of PCDD/Fs in some samples of the ongoing biomonitoring should be done
