Environmental forensics is defined as the systematic and scientific evaluation of physical, chemical, and historical information to develop conclusions about the source or age of environmental contamination. It uses analytical techniques from various fields like chemistry, biology, and geology to investigate contamination sources, extent of contamination, and provide evidence for legal actions. Environmental forensics can be applied to issues like contaminated sites, air and water pollution, and waste disposal. Key techniques include chemical fingerprinting, isotopic analysis, and examining indicators in the environment like chemical, microbial, plant, and animal indicators to identify contamination sources. Toxicity assessment methods are also important tools to evaluate the effects of contaminants on living organisms and ecosystems.

2. DEFINITION
• Environmental forensics is defined as the systematic
and scientific evaluation of physical, chemical and
historical information for the purpose of developing
defensible scientific and legal conclusions regarding
the source or age of a contaminant release into the
environment.

3. • Environmental forensics is a multidisciplinary scientific approach
that uses various analytical techniques and methods to investigate and
identify sources of contamination in the environment, determine the
extent and severity of contamination, and provide evidence to support
legal or regulatory actions.
• It involves the application of principles from various fields such as
chemistry, biology, geology, and environmental science to solve
environmental problems.
• Environmental forensics can be used to investigate a range of
environmental issues, including contaminated sites, air pollution,
water pollution, and waste disposal.

5. TECHNIQUES OF ENVIRONMENTAL FORENSICS
• The main
application of
environmental
forensics
techniques is
basically for the
contaminant age
dating & source
identification.
S.No Techniques
1 Aerial photo intrepretation/photogrammetry
2 Chemicals associate with discrete chemical processes
3 Identification of the manufacturer of a particular product
4
Chemical additives
and/or impurities
5 Chemical profiling
6 Degradation modeling
7 Corrosion models
8 Contaminant transport modeling
9 Surrogate chemical analysis
10
Chronological changes in
chemical processes resulting is diagnostic markers
11 Compound specific isotopic analysis
12
Polychlorinated biphenyl (PCB) congener analysis and
degradation product ratio
analysis

6. Contaminants where Environmental Forensics
is used
• Petroleum hydrocarbons (refined/unrefined)
• PAHs
• Chlorinated solvents (PERC)
• PCBs/PCDDs/PCDF
• Metals (selected)
• VOCs
• Methane (coal bed methane)
• Pesticides (persistent/non persistent)
• Other persistent organic pollutants

7. INDICATORS OF ENVIRONMENTAL FORENSICS
Indicators are physical, chemical, or biological parameters that are used
to detect and quantify environmental contamination.
Indicators are used in environmental forensics to help identify the
presence of contaminants and determine their source.

8. INDICATORS
S.No Indicators Application Example
1 Chemical fingerprints
The analysis of chemical compounds can reveal
unique "fingerprints" that can be used to identify
the source of contamination.
Analysis of polycyclic aromatic hydrocarbons
(PAHs) to determine the source of petroleum
contamination.
2 Isotopic analysis
The analysis of chemical compounds can reveal
unique "fingerprints" that can be used to identify
the source of contamination.
Analysis of nitrogen and sulfur isotopes to
determine the source of nitrogen and sulfur
contamination in groundwater.
3 Microbial analysis
Microbial communities can provide clues to the
source of contamination, as different types of
bacteria and fungi are associated with different
sources of pollution.
Analysis of bacteria in soil to determine the
source of fecal contamination in surface
water.
4 Physical evidence
Physical evidence such as containers, pipes, and
soil samples can provide important clues to the
source of contamination.
Identification of a buried drum containing
hazardous waste as the source of
contamination.

9. 5 Historical records
Historical records such as
property ownership, land use,
and industrial activities can help
identify potential sources of
contamination.
Review of property ownership
records to determine past land
use activities and potential
sources of contamination.
6 Geospatial analysis
The use of geospatial analysis can
help identify areas of potential
contamination, and can help
identify potential sources of
pollution.
Mapping of groundwater
contaminant plumes to
determine potential sources of
contamination.
7 Toxicological analysis
The analysis of biological samples
such as blood or urine can
provide information about the
exposure of individuals or
populations to contaminants.
Analysis of lead levels in
children's blood to determine
exposure to lead in the
environment.

10. BIOINDICATORS
• Bioindicators are living organisms such as plants, planktons, animals,
and microbes, which are utilized to screen the health of the natural
ecosystem in the environment.
• They are used for assessing environmental health and biogeographic
changes taking place in the environment.
• Each organic entity inside a biological system provides an indication
regarding the health of its surroundings such as plankton responding
rapidly to changes taking place in the surrounding environment and
serving as an important biomarker for assessing the quality of water
as well as an indicator of water pollution.
• Even the health of aquatic flora is best reflected by plankton, which
acts as an early warning signal

11. Advantages of using Bioindicators
• Biological impacts can be determined.
• To monitor synergetic and antagonistic impacts of various pollutants
on a creature.
• Early stage diagnosis as well as harmful effects of toxins to plants, as
well as human beings, can be monitored.
• Can be easily counted, due to their prevalence.
• Economically viable alternative when compared with other
specialized measuring systems.

12. TYPES OF
BIOINDICATORS

13. Plant indicator
• Plants are used as very sensitive tools for prediction and recognition of
environmental stresses.
• Lichens generally found on the trunks of trees and rocks are composed
of algae and fungi both. They react to ecological changes in forests,
including changes in the structure of the forest, air quality, and climate.
• Environmental stress can be indicated by the disappearance of lichen in
forests as caused by changes such as increases in the level of sulfur
dioxide (SO2), pollutants of sulfur and nitrogen (N2).
• Wolffia globosa is an important tool for showing cadmium sensitivity
and also used for indicating cadmium contamination.
• Changes in the diversity of species of phytoplankton, including Euglena
clastica, Phacus tortus, and Trachelon anas, indicate the pollution of
marine ecosystem

14. Flow chart of planktons indicating pollution (lake condition).

15. Types of phytoplankton and its indications

16. Examples of Bio-indicator : Plants
Bioindicator Found in Indicator of
Diatoms
Freshwater, marine and brackish
water
Water quality, specifically the level of nutrients and organic matter.
Cyanobacteria
Freshwater, marine and brackish
water
Water quality, specifically the level of nutrients and organic matter. Some
species can produce toxins that can be harmful to human health and other
organisms.
Sphagnum moss Bogs and wetlands
Changes in climate and atmospheric pollution. Can be used to reconstruct
past environmental conditions.
Lichens
Soil, rocks, trees and other
surfaces
Air pollution, specifically the level of sulfur dioxide and other pollutants.
Mycorrhizal fungi Roots of plants and trees
Soil quality, specifically the level of nutrients and organic matter. Can also
indicate the presence of contaminants in the soil.
Ferns
Forests, wetlands and other
habitats
Changes in soil moisture and water quality. Some species can also
accumulate heavy metals in their tissues.
Weeds
Agricultural fields and disturbed
habitats
Changes in soil quality and the presence of contaminants, such as
pesticides and herbicides.
Trees
Forests, urban areas and other
habitats
Air pollution, specifically the level of particulate matter, ozone and
nitrogen dioxide. Can also indicate changes in soil quality and the presence
of contaminants.

17. Animal indicators
• Variations in the populations of animals may indicate harmful changes
caused due to pollution into the ecosystem.
• Changes in the population density may indicate negative impacts to
the ecosystem.
• Changes in populations may be a result of the relationship between
populations and food sources; if food resources become scarce and
cannot provide for the population demand reduction of said
population will follow.

18. • Animal indicators also help in detecting the amount of toxins present
in the tissues of animals.
• Frogs are also Bioindicators of quality of environment and changes in
environment. Frogs are basically influenced by changes that take
place in their freshwater and terrestrial habitats. This makes them
important Bioindicators of ecological quality and change.
• Zooplanktons like Alona guttata, Mesocyclops edax, Cyclops, Aheyella
are zone-based indicators of pollution.
• Invertebrates can also be Bioindicators; aquatic invertebrates tend to
be bottom feeders (also known as Benthos or macro invertebrates),
living near the bottom of water bodies. These types of Bioindicators
may be particularly powerful indicators of watershed health as they
are not difficult to distinguish in a lab, frequently live for more than
one year, have restricted mobility, and are integrators of ecological
condition

19. Types of zooplanktons and its indications

20. Examples of Bio-indicator : Animals
Animal Indicator Found in Indicator of
Fish Freshwater and marine habitats
Water quality, specifically the level of nutrients and organic matter, as well
as the presence of contaminants such as heavy metals and organic
pollutants.
Birds
Various habitats, including forests,
wetlands, and urban areas
Ecosystem health, habitat quality, and exposure to contaminants. Changes
in bird populations and behavior can indicate changes in environmental
conditions.
Bats
Forests, wetlands, and other
habitats
Changes in insect populations and exposure to contaminants such as
pesticides and heavy metals. Can also indicate changes in habitat quality.
Amphibians
Wetlands, ponds, and other
aquatic habitats
Water quality, specifically the level of nutrients and organic matter, as well
as the presence of contaminants such as pesticides and heavy metals. Can
also indicate changes in habitat quality.
Bees and other pollinators
Various habitats, including
agricultural fields and urban areas
Changes in habitat quality, exposure to contaminants such as pesticides,
and changes in plant communities.
Mammals
Various habitats, including forests,
grasslands, and urban areas
Exposure to contaminants such as heavy metals, pesticides, and air
pollutants. Can also indicate changes in habitat quality and ecosystem
health.

21. Microbial indicators
• Microorganisms are often used as health indicators of aquatic and
terrestrial ecosystems. Due to their abundance, they are easy to test
and readily available. Some microorganisms when exposed to
cadmium and benzene contaminants develops new proteins known
as stress proteins which can be used as early warning signs.
• Microorganisms are an important part of oceanic biomass and are
responsible for the majority of productivity and nutrient cycle in a
marine ecosystem. Microorganisms have a rapid rate of growth, and
react to even low levels of contaminants and other physicochemical
and biological changes

22. • Microbial indicators can be used in a variety of ways to detect environmental
pollutants in water including the use of bioluminescent bacteria.
• The presence of toxins in waters can be easily monitored either by changes in
the digestion system of microbes which is hindered or disturbed by the
presence of toxins which may result in changes in the amount of light emitted
by the bacteria.
• In comparison to other available traditional tests, these tests are very quick to
monitor; however, their limitation is they can only indicate the changes in the
organisms due to presence of toxins.
• One such example is the bacterium Vogesella indigofera which reacts to heavy
metals quantitatively. Under the influence no metal pollution, this bacterium
produces blue pigmentation which is an important marker of morphological
change that has taken place which can be effectively observed visually.

23. Examples of Bio-indicator : Microbes
Microbial Indicator Found in Indicator of
Coliform bacteria Water and soil
Faecal contamination, which can indicate the presence of
pathogens and potential health risks.
Nitrogen-fixing bacteria Soil and plant roots Soil quality, specifically the level of nitrogen and organic matter.
Methanogenic archaea
Wetlands, marshes, and other
anaerobic habitats
Changes in carbon cycling and decomposition rates. Can also
indicate changes in soil quality and the presence of contaminants.
Sulfate-reducing bacteria
Marine and freshwater
sediments
Changes in sulfur cycling and the presence of contaminants such as
heavy metals and organic pollutants.
Acidophilic bacteria
Acidic environments such as
acid mine drainage
Presence of acid-generating contaminants and changes in soil
quality.
Bioluminescent bacteria
Marine and freshwater
habitats
Changes in water quality and the presence of contaminants such as
heavy metals and organic pollutants.
Indicator fungi Soil and plants
Soil quality, specifically the level of organic matter and the
presence of contaminants.

24. Toxicity assessment methods
• Environmental toxicity assessment methods refer to a set of techniques and
approaches used to evaluate the potential adverse effects of chemical and
physical agents on living organisms and ecosystems in the environment. These
methods are critical in identifying and quantifying the risks posed by these
agents to human health and the environment.
• The purpose of an environmental toxicity assessment is to determine the
concentration or dose of a substance that may cause harm to the
environment or living organisms.
• This information is important in establishing regulatory limits, developing risk
management strategies, and making informed decisions about the use and
disposal of chemicals and other agents.

25. • These methods vary widely depending on the type of substance being
evaluated, the organism or ecosystem being studied, and the specific endpoint
of interest.
• Some common methods include Acute And Chronic Toxicity Tests, Bioassays,
Microtox Assays, Enzyme Assays, Cell Culture Assays, Biomarker Assays,
Sediment Toxicity Tests, And Ecotoxicological Risk Assessments.
• Acute And Chronic Toxicity Tests involve exposing organisms to a substance for
a short or long period to determine its effects on their survival, growth, and
reproduction.
• Bioassays And Microtox Assays are used to detect the presence and extent of
toxic substances in the environment.
• Enzyme assays measure changes in enzyme activity in response to toxic
substances, while cell culture assays assess toxicity on a cellular level.

26. • Biomarker Assays measure changes in gene or protein expression in response
to toxic substances, and sediment toxicity tests assess toxicity of sediment
samples.
• Finally, Ecotoxicological Risk Assessments are used to determine the potential
risks of a chemical or substance to the environment and living organisms.
• Environmental toxicity assessment methods are an important tool for
protecting human health and the environment.
• They are used in a variety of settings, from evaluating the safety of new
chemicals and pharmaceuticals to assessing the risks posed by pollution and
contamination in our air, water, and soil.
• By using these methods, we can make informed decisions that balance the
benefits of chemical and industrial processes with their potential risks to the
environment and human health.

27. Case
Assessment
Method
Applications Examples
Oil spill in marine
environment
Acute toxicity tests
Assess immediate, short-term effects of
chemicals on living organisms
LC50 test in fish and crustaceans to
determine the toxicity of oil spills on
marine life.
Agricultural runoff
in freshwater
systems
Chronic toxicity
tests
Assess long-term effects of chemicals on
living organisms
Chronic toxicity test in algae and fish to
determine the effects of agricultural
runoff on freshwater systems.
Industrial effluent
discharge into rivers
Bioassays
Detect presence and extent of toxic
substances in the environment
Bioassay using Daphnia to detect the
presence of toxic substances in river
water.
Contaminated
drinking water
Microtox assays
Detect presence of toxic substances in water
or soil samples
Microtox assay to detect the presence of
toxic substances in drinking water
samples.
Pesticide exposure
in agricultural
workers
Enzyme assays
Measure changes in enzyme activity in
response to toxic substances
Acetylcholinesterase inhibition assay to
measure pesticide exposure in
agricultural workers.

28. Pharmaceutical
drug development
Cell culture assays
Assess toxicity of substances on a cellular
level
Cell viability assays to assess cytotoxicity
of new pharmaceutical compounds.
Environmental
pollution from
industrial sources
Biomarker assays
Measure changes in gene or protein
expression in response to toxic substances
Gene expression analysis of liver cells to
identify potential toxicity of pollutants on
human health.
Sediment
contamination from
historical industrial
activities
Sediment toxicity
tests
Assess toxicity of sediment samples
Benthic community toxicity test to assess
toxicity of sediment from a contaminated
river.
Environmental
impact assessment
of a new
development
project
Ecotoxicological risk
assessments
Determine potential risks of a chemical or
substance to the environment and living
organisms
Ecotoxicological risk assessment of a new
offshore wind farm.

29. THANK YOU