ENSC 201 Test 3

Air pollutant definition

Airborne substances released into the atmosphere that have the potential to harm human health and the environment

1. Human health effects of smog

2. Acidification of surface waters

3. Crop and forest damage

4. Damage to built structures

Major concerns for air pollution

____% of population breathes air exceeding limits for exposure to pollutants

99%

____ million deaths attributed to air pollution in 2021

9

Air pollutants

____ ____ are linked to respiratory diseases, stroke, and heart diseases

2.4

_____ billion people estimated to be exposed to dangerous levels of air pollution

1. Burning of fossil fuel

2. Vehicle emissions

3. Industrial processes

Sources of air pollutants

1. Gases

2. Aerosols

3. Particulates

Types of air pollutants

Examples of gas air pollutants

CH4, CO, CO2, SO2

Examples of aerosol air pollutants

Sulphates, fine droplets of organic material

Examples of particulates

Soot (carbon), oxides and salts of metals and other inorganics, chemical mixtures of particles with organic substances absorbed onto them

Tropospheric ozone

Formed by the interaction of sunlight with volatile organic compounds and nitrogen oxides

Tropospheric ozone

Increased temperatures accelerate ______ _______ formation

Nitrogen oxides, volatile organic compounds

Fossil fuel combustion from vehicles and industrial plants are a major source of _____ ______ and _____ ______ ______

1. Toxic to human/plant health

2. Contributes to global warming by trapping heat in the atmosphere

3. Reduces carbon uptake, further contributing to climate change

Effects of tropospheric ozone

Thermal inversion

Suppress vertical air movement so that atmospheric contaminants can’t rise out of the lower layer of air

Great Smog

London 1952, period of cold weather, lots of coal burning, anticyclone weather event, inversion trapped air, ~4000 deaths and 100000 illnesses, lead to the Clean Air Act and phase out of coal burning

1. Bronchitis

2. Lung infections

3. Impaired lung function

4. Asthma

5. Carcinogenicity

Chronic effects of air pollution

1. Long range goals to decrease ozone in air

2. Emission controls for vehicles

3. Warnings for susceptible persons to avoid exposure

Examples of risk management

Perfluoroalkyl and polyfluoroalkyl substances (PFAS)

Global pollutant, class of over 4700 human made

East Palestine train derailment

Train derailment due to overheating of a wheel bearing, some cars were carrying hazardous materials, controlled release and burn of vinyl chloride to prevent a catastrophic explosion

EPA response to East Palestine train derailment

ASPECT team response, air-quality testing, mobile analytical laboratory

ASPECT stands for…

Airborne Spectral Photometric Environmental Collection Technology

ASPECT team

Specializes in rapid, on-site air monitoring and analysis during hazardous materials incidents

Air sampling

Collecting an air sample over a period of time that is then sent to a laboratory for analysis to identify and quantify specific compounds

Air monitoring

Uses electronic devices to provide real-time readings of airborne contaminants

Air monitoring in East Palestine

U.S. EPA deployed mobile detection equipment and stationary equipment to conduct air monitoring, collected measurements for lower explosive limits, volatile organic compounds, etc.

Air monitoring locations in East Palestine

Schools, residential areas, government buildings, upwind, in, and downwind of the derailment area, and mobile teams to collect general readings throughout the community

Air sampling in East Palestine

U.S. EPA is collecting outdoor air samples for volatile organic compounds including vinyl chloride, etc. Locations were selected upwind of the train derailment area, and downwind areas

Indoor air screening in East Palestine

U.S. EPA assisted with screening of more than 500 homes within the evacuation zone

Soil removal process

Conducting soil sampling, removing tracks in sections, removing soil, and placing it in a staging area for testing and disposal

Vinyl chloride

Used to make PVC, makes a variety of plastic products including pipes, wire coatings, and packaging materials, breaks down to hydrochloric acid, formaldehyde, and carbon dioxide

Breathing, eating, drinking, dermal

Routes of exposure of vinyl chloride

Trace = 1 ppm, 44 ppm in landfills

Normal air levels of vinyl chloride

Yes, it doesn’t bioconcentrate

Can vinyl fluoride dissolve in groundwater?

1000-8000 ppm, can smell a sweet odor

Acute toxicity of vinyl chloride

25000 ppm, but you can recover after breathing fresh air

When you pass out from vinyl chloride

Yes, through exposure to 50 ppm over long periods of time, in animals and humans

Is vinyl chloride a carcinogen?

Yes, at a level of 5000 ppm

Is vinyl chloride a teratogen?

1. n-butyl acrylate

2. Ethyhexyl acrylate

3. Ethylene glycol monobutyl ether

4. Isobutylene

5. Acrolein

Compounds of concern

Next steps for East Palestine

1. Clean up site

2. Class action lawsuits against Norfolk Southern Railway

3. Improved transparency conveying uncertainties

4. Long term health impact studies

5. Continued environmental monitoring

Lessons from East Palestine train derailment

1. Heat detectors around wheel carriages in trains should be installed

2. Electronically controlled pneumatic brakes should be equipped

3. Wayside defect detectors should be placed with the right spacing and temperature thresholds

Pharmaceuticals, personal care products

________ and ______ _______ _______ are emerging contaminants

Pharmaceuticals

______ contain many potential environmental toxicants, when consumed, a portion is excreted into the sewage system

1. Soap

2. Creams

3. Lotions

4. Perfumes

5. Shampoos

Examples of personal care products

EPPs

Environmentally persistent pollutants

Pharmaceuticals

In the 1990s, some _____ were detected in the water, especially in water affected by sewage treatment plant effluent

Pharmaceuticals

In the 2000s, some _____ were detected in drinking water, lower levels than in sewage effluent, linked to new analytical technologies

1. Individual use

2. Hospitals

3. Pets

4. Agriculture

5. Industry

Examples of sources of pharmaceuticals in the environment

Pharmaceuticals

______ have potential for long-term impacts on ecosystem health, can persist into future generations of non-target organisms

PPCPs

Pharmaceuticals and personal care products

No

Are there regulatory guidelines for exposure to PPCPs?

Scientific information is not completely available

Why are there no regulatory guidelines for PPCPs?

1. Acetaminophen

2. Codeine

3. Antibiotics

4. Hormones

5. Over 165 individuals pharmaceuticals and PCPs

Substances found in the Great Lakes in 2014

New technology, aging population, more people taking more drugs

Why were so many PPCPs found in the Great Lakes in 2014?

Intersex fish due to PPCPs in Great Lakes

Males develop eggs in their testes, puts survival of some species in jeopardy

Hyderabad, India

Sites in the direct environment of bulk drug manufacturing facilities in _____, ______ and nearby villages were contaminated with antimicrobials

95%

____% of samples from Hyderabad contained high levels of bacteria and fungi resistant to antibiotic drugs, resulting in thousands of newborns dying from multidrug-resistant infections every year

WWTP

Waste water treatment plant

Two stages of wastewater treatment

Primary (physical separation of oil and grease, dense particles) and secondary (treatment with bacteria to biodegrade contaminants)

Goal of wastewater treatment

Reduce oxygen demand, nitrogen and phosphorous nutrients, pathogens, and contaminants/toxicants

Primary, secondary

_____ and _____ stages of wastewater treatment are required if discharging into fresh water

Problem with WWTP

They were never designed to remove molecules like pharmaceuticals, some compounds are biodegraded by secondary treatment bacteria, others are not

Where to start with pharmaceuticals regulations

Need a basis for saying drinking water is safe, environmental toxicity endpoints are available but not likely good estimates of human endpoints

Pharmaceuticals

______ are biologically active, possible toxicity may or may not be through the same mode of action, many are endocrine disrupting chemicals

EDCs

Endocrine disrupting chemicals

Proposed solution for pharmaceuticals in water regulations

Use minimum therapeutic dose as acceptable environmentally safe level

Solutions to reduce levels of pharmaceuticals in water

1. Reduce improper disposal of medications

2. Restrict veterinary pharmaceuticals

3. Reduce land application of manure

4. Improve industrial effluent treatment

Main solution to reduce levels of pharmaceuticals in water

Reduce levels of pharmaceuticals in treated sewage before release

Improved wastewater treatment

Tertiary step specifically targeting PPCPs and similar molecules, may include chemical processes like ozone, UV, or both

Precautionary principle

Taking preventative measures even when scientific certainty is lacking

Precautionary principle

_____ _____ is often not effectively applied when the cost of preventative measures is very high, and the perceived risk is relatively low or uncertain (ex. upgraded sewage treatments would cost trillions globally)

Per/polyfluoroalkyl substances (PFAs)

Fluoridated substances that contain at least 1 fully fluoridated methyl or methylene carbon atom without any H/Cl/Br/I atom attached to it

1930s

Per/polyfluoroalkyl substances were discovered in early _____

PFAs

_____ have a hydrophilic head and a hydrophobic tail

1. Water/oil repellency

2. Chemical and thermal resistance

3. Friction reduction

4. Surfactant properties

Properties of PFAs

WWTP don’t have adequate treatment systems in place to remove all PFAs from effluent, eventually find their way into the environment

Environmental impacts of PFAs

PFAs

______ have a very long residence time, strongest bond in organic chemistry

PFAs

______ are found in virtually all environmental matrices (groundwater, rainwater, soil, and ocean)

PFAs

Regulations for _____ only target the tip of the iceberg, don’t cover the diversity of _______

1. Literature reviews

2. Toxicity tests conducted in a lab and in the field

How to predict risk

Literature reviews

Published articles regarding the effects of different contaminants on many model organisms

Toxicity tests

Expose groups of organisms to a range of doses/concentrations for a set period of time and record responses

1. Controlled experiments

2. Rapid and relatively inexpensive

3. Often conducted with individual substances

Properties of toxicity tests

SOPs

Standard operating procedures

Standard Operating Procedures (SOPs)

Detailed instructions for performing commonly used techniques aiming for consistency and efficiency

Sources of SOPs

International Organization for Standardization (ISO), Organization for Economic Cooperation and Development (OCED)

Lethal and sublethal

2 forms of toxicants effects at the individual level

Acute lethality (death followed by exposure within 96 hours) and chronic lethality (death followed by prolonged exposure)

2 groups of contaminant lethality

Developmental effects

Conventional assays to measure _____ _____ often use highly understood model organisms

Frog embryo teratogenesis assay

Use clawed frog embryos to determine if a toxicant can cause developmental malformations

1. Produce large amounts of eggs and sperm

2. Has well-documented stages of development and metamorphosis

Why are frog embryos used to measure developmental effects?

PCB congeners

____ ____ can act as estrogen agonists in red-eared slider turtles, can cause embryos to develop into females

Behavioural toxicology

Study of abnormal behaviours produced by toxicant exposure (ex. activity level, predation, feeding, etc.)

1. Some behaviours are hard to score

2. High variability in some behaviours

3. Hard to extrapolate from lab to wild settings

3 shortcomings of behavioural toxicology

1. Time consuming and costly

2. Requires large numbers of test organisms

Disadvantages of conventional toxicity tests

Novel approach methods

Any technology, methodology, approach, or combination that informs chemical hazard and risk assessment method

Novel approach methods

____ _____ _____ help in the replacement, reduction, and/or refinement of animal toxicity testing and allows for thorough assessment of chemicals

1. Avoid or replace the use of animals

2. Minimize the suffering and improve animal welfare

3. Minimize the number of animals used per experiment

Replacement, refinement, reduction

Replacement

Avoid use of whole sentient animals, in vitro instead of in vivo