A description of carcinogens covering all aspects.

1. MADAN MOHAN MALAVIYA UNIVERSITY OF
TECHNOLOGY, GORAKHPUR (U.P.) INDIA
TOPIC : CARCINOGENS
Presented To :
Shri Ram Chaurasia Sir
(Associate Professor)
MMMUT
Presented By :
Akansha Sinha
M. Tech. (1st year)
Environmental Engineering
(2019013204)

2. OBJECTIVES
 Carcinogens
 Environmental factors causing cancer
 Carcinogenesis
 Types of Carcinogens
 Determination of Carcinogens
 Various agencies classifying Carcinogens
 Reduction of exposure to Carcinogens
 Disposal of Carcinogenic substances

3. What is Carcinogen ?
• A Carcinogen is any substance, radionuclide, or radiation that
promotes Carcinogenesis, the formation of cancer.
• The definition of Carcinogen proposed by IARC is - a Carcinogen
denotes any agent, exposure to which is capable of increasing the
incidence of malignant neoplasia (IARC 1993).
• CANCER - A disease in which abnormal cells divide uncontrollably
and destroy body tissue.
• It is the result of changes in a cell’s DNA – its genetic “blueprint.”
Some of these changes may be inherited from our parents. Others may
be caused by outside exposures.

4. Environmental factors causing cancer are :
• Lifestyle factors (nutrition, tobacco and alcohol use, physical
inactivity, etc.)
• Naturally occurring exposures (ultraviolet light, radon gas, infectious
agents, etc.)
• Medical treatments (radiation and medicines including
chemotherapy, hormone drugs, drugs that suppress the immune
system, etc.)
• Workplace exposures
• Household exposures
• Pollution

5. Carcinogenesis
The cancer-generating
process called
Carcinogenesis is a multi-
step process, usually slow,
linked to mutagenesis.
This process goes through
distinct stages such as
initiation, promotion and
progression.

6. Types of Carcinogens :
• Chemicals/Substances : Like asbestos in insulation can lead to lung
cancer and mesothelioma.
• Environmental radiation : Like ultraviolet radiation from the sun is the
cause of skin cancer.
• Medical radiation : Both radiation used medically for diagnostic tests
and that used to treat cancer are considered Carcinogens.
• Viruses : Like human papillomaviruses which cause oral cancer and
cervical cancer, and hepatitis C, which can cause liver cancer.
• Some medications: Some chemotherapy drugs (such as Cytoxan) and
hormonal therapy can raise the risk of cancer.
• Lifestyle factors: Smoking and obesity are both Carcinogens in that they
can be responsible for the mutations which result in cancer.
• Pollution: Both outdoor and indoor air may contain pollutants that are
Carcinogenic.

7. How do researchers determine if something is a Carcinogen?
For this scientists use lab tests on cell cultures and animals, or
epidemiology studies, which look at human populations.
What lab studies can show :
Almost all Carcinogens are first tested on and found to cause cancer in lab
animals then are later found to cause cancer in people. Most studies of
potential Carcinogens expose the lab animals to doses that are much
higher than common human exposures.

8. What Epidemiology studies (studies in people) can show :
Epidemiology studies look at different groups of people to determine
which factors might be linked to cancer.
By combining data from the studies, scientists do their best to make an
educated assessment of whether something can cause cancer.
When the evidence is conclusive, the exposure or substance is labeled as
a Carcinogen.
When the available evidence is compelling but not felt to be conclusive,
the exposure or substance may be labeled as a probable Carcinogen.
When there is limited evidence that is far from being conclusive, the
exposure or substance may be labeled as a possible Carcinogen.

9. Who determines how Carcinogens are classified?
Several national and international agencies review the available
evidence to try to determine the cancer-causing potential of
different substances.

10. International Agency for Research on Cancer
• The International Agency for Research on Cancer (IARC) is the
specialized cancer research agency of WHO.
• IARC promotes cancer prevention and communicates scientific results to
the general public and the media.
• IARC has evaluated the cancer-causing potential
into these groups:
Group 1: Carcinogenic to humans
Group 2A: Probably Carcinogenic to humans
Group 2B: Possibly Carcinogenic to humans
Group 3: Not classifiable as to its Carcinogenicity in humans

11. International Agency for Research on Cancer
Group 1: Carcinogenic to humans
• Acetaldehyde (from consuming alcoholic beverages)
• Alcoholic beverages
• Ionizing radiation (all types)
• Solar radiation
• Tobacco, smokeless
• Tobacco smoke, secondhand
• Tobacco smoking
• Ultraviolet (UV) radiation, including UVA, UVB, and UVC rays
• Welding fumes
• Wood dust
• X- and Gamma-radiation

12. National Toxicology Program
• The National Toxicology Program (NTP) is formed from parts of several
US government agencies, including the National Institutes of Health (NIH),
the Centers for Disease Control and Prevention (CDC), and the Food and
Drug Administration (FDA).
• The NTP updates its Report on Carcinogens (RoC) every few years.
• The Report on Carcinogens identifies 2 groups of agents:
 Known to be human Carcinogens
 Reasonably anticipated to be human Carcinogens
• The current version of the RoC includes about 250 substances.

13. National Toxicology Program 14th Report on Carcinogens
• Arsenic and inorganic arsenic compounds
• Asbestos
• Benzene
• Beryllium and beryllium compounds
• Coal tars
• Mineral oils (untreated and mildly treated)
• Nickel compounds
• Radon
• Solar radiation
• Ultraviolet (UV) radiation, broad spectrum
• Wood dust
• X-radiation and gamma radiation

14. Other agencies and groups
• The Environmental Protection Agency (EPA)
• The CDC’s National Institute for Occupational Safety and Health (NIOSH)
• The Food and Drug Administration (FDA)
• The National Cancer Institute (NCI)
• California Environmental Protection Agency (CalEPA)

15. The American Cancer Society’s role
• The American Cancer Society (ACS) contributes in many ways to
evaluating how environmental factors affect a person's likelihood of
developing cancer.
• The ACS does not directly evaluate whether a certain substance or
exposure causes cancer. Instead, the ACS looks to national and
international organizations such as the NTP and IARC.

16. To reduce your exposure to Carcinogens :
 Be informed
To learn about what may be harmful, check out our list of environmental
concerns and chemicals in the workplace. You’ll also find out how to reduce
your exposure or protect yourself when you’re around Carcinogens.
 Make safer decisions
For example, avoid idling your vehicle, or dig out weeds at their roots instead
of using pesticides.
 Follow safety instructions when using, storing and disposing of
harmful materials or chemicals
Read and carefully follow the manufacturers’ directions for safely using and
storing hazardous chemicals at home and at work.

17. How to dispose off Carcinogenic substances :
Carcinogenic substances should never be disposed of through drains or
by evaporation into the atmosphere, nor should they be buried since they
might be released later.
Carcinogenic substances should be treated in such a way that:
• The degradation products are non-toxic and non-Carcinogenic.
• The procedures involved for treatment and disposal do not result in
exposure to these substances of personnel in charge of the work.
• The procedures involved for treatment and disposal do not result in
contamination of equipment or space.

18. References
https://www.cancer.org/cancer/cancer-causes/general-
info/known-and-probable-human-Carcinogens.html
https://link.springer.com/chapter/10.1007%2F978-3-642-71342-
2_3
https://www.cancer.ca/en/prevention-and-screening/reduce-
cancer-risk/make-informed-decisions/know-your-
environment/3-smart-ways-to-reduce-your-exposure-to-
Carcinogens/?region=on
https://ntp.niehs.nih.gov/whatwestudy/assessments/cancer/roc
/index.html?utm_source=direct&utm_medium=prod&utm_cam
paign=ntpgolinks&utm_term=roc14
https://monographs.iarc.fr/agents-classified-by-the-iarc/