Hazardous Substances in Footwear Industry: An approach for better Human
Sujit Kumar Basu1 & Pankaj Kumar Tyagi1
Asstt. Professor, University Polytechnic, Faculty of Engg. & Tech., AMU.
E-mail : firstname.lastname@example.org, email@example.com, Mobile: 09456668545
Abstract :- In today’s global scenario where plenty of strict regulations are imposed from
different national and international platforms and a continuous increasing level of
consciousness on the use of hazardous substances during the processing of consumer
goods, the manufacturers have already been started to smell an increasing pressure to be
able to demonstrate progressive improvements in the working conditions—not only in their
factories but also those of their allied suppliers. In footwear industry too, many hazardous
volatile organic solvents, chemicals and substances like Acetone, Ethyl Acetate, Toluene,
Di-Chloromethane, MEK, Di-Methyl Formaldehyde, Pentachlorophenol, Azo Dyes,
Isocyanates, Dust of Leather Fibers consist of heavy metals like Chromium VI, Nickel,
Cadmium etc. are widely used or produced during its manufacturing operations. By default
these come into direct contact to the operators in their everyday work and to the end
users, which lead to a great concern over their health issues specially for the too young or
too old and pregnant women. It covers like different skin problems, eyes problems,
respiratory problems, disorder in central nervous system and may lead to a permanent
damage to liver, kidneys and various type of cancers. In this paper we have tried to identify
the most hazardous substances used in the footwear industry, to understand their
immediate and long term ill impact over human health, to recognize their risk management
and to find out some approaches to replace or to reduce their uses by natural substitute or
by using better technology & equipments for protection and monitoring.
Introduction :- Apparently footwear industry looks negligible polluted and hazardous in
compare to leather and other consumer goods making industries but it is quite true that it is
very less in term of pollution but in term of producing hazardous substances it counts a
significant scale. A huge range of substances and processes are used within the footwear
industries. Everyday workers at work are exposed to substances which cause significant
concern over the different types of short and long type heath problems to them. An
enlarged contribution of its hazardous substances are mainly different types of Volatile
Organic Solvents. Solvents have been identified as major environmental pollutants and are
supposed to be phased out under the Montreal Protocol. Less consciousness from both
the operators and the proprietors, proper education to monitor and control and overall lack
of strict regulations and their implementations from the local administration are some
lacunas for arising those critical human health problems.
Hazardous Substances in Footwear Manufacturing Operations :-
Operation Process / Process Type of Hazard
Upper Fitting / Lining Natural rubber latex adhesives. Ammonia in low concentration.
Polychloroprene adhesives. Range of Solvents.
Stitch Marking Inks. Light petroleum spirit.
Toe Puff and Counter Stiffener Solvent Activators. Range of Solvents.
Upper and Sole Preparation. Solvent wipes/primers. Range of Solvents.
Roughing / scouring Dust (leather, rubber,polymers)
Bottom fillers. Cork composition fillers. Range of Solvents.
Upper and Sole Cementing. Polychloroprene adhesives. Range of Solvents.
PU two-part adhesives. Isocyanates, range of solvents.
Sole Moulding PVC Soling Compounds PVC fumes, Plasticizers.
PU Soling Compounds. Isocyanates.
Mould & Injection Head Methylene Chloride.
Mould releasers. Small Silicon particles.
Heel/sole lacquering /painting Lacquers/finishes Range of Solvents.
Shoe room/finishing Cleaners. Light petroleum spirit, ethanol,
Finishes Dressings. Range of Solvents.
Comparison of Occupational Exposure Standards (OES) for some Hazardous
Solvents ( in parts / million for an 8 hours period ) :-
Note :- The lower the OES the higher the risk.
Chemical UK USA ILO Indonesia China
Acetone 500 500 750 750 750
Ammonia 25 25 25
Benzene* 3 0.5 10 10
Dichloromethane* 100 50 50 50
Ethyl acetate 200 400 400 400 400
Hydrogen Chloride 1 0 5 5
Isocyanate Hardener* (Note -1)
Methyl ethyl ketone 200 200 200 200 200
Styrene* 100 100 50 50
Toluene 50 50 50 50 100
(*) These are chemicals need particular attention.
( Note -1) Isocyanate Hardener in two part adhesives are extremely toxic but the amount of
free isocyanate present in the atmosphere is likely to be very low. There is a MEL (Maximum
Exposure Limit) given in U.K. EH40/2002 in mg/m3 of 0.02, which is extremely low.
Health Risks from Hazardous Substances:-
Skin Problems :- Substances can cause local irritation but in some cases, without any
notice there can be extreme sensitivity to a particular chemical leading to dermatitis. If this
occurs just small amounts of the chemical can provoke an attack. Some chemicals like
Toluene can be absorbed through the skin into the bloodstreams.
Eye Problems :- Some substances in the air, particularly ammonia cause irritation to the
eyes causing reddening and watering.
Respiratory Problems :- Breathing of certain substances can cause irritation to the nose,
windpipe and lungs. Sore throats, coughs and colds are possible signs of excess
Central Nervous System :- Many solvents cause light headedness or drowsiness. This is
particularly dangerous while the operators are nearby or actually operating machines, an
accident is more likely to occur.
Long Term Problems :- Prolonged exposure to some solvents can lead to permanent
damage to liver, kidneys and be a trigger for various kinds of cancer.
Fire Risks from Hazardous Solvents :- Organic solvents tend to be very volatile, i,e.
they give off heavy vapours. Solvents are classified as non-flammable and flammable.
However, non-flammable solvents can create a hazard when they exposed to high
temperature and give off toxic by-products while in contact to the fire. The most obvious
risk is when there is a leakage from a container of volatile flammable solvent. The solvent
vapour being heavier than air, stays at ground level, reaches a source of ignition, ignites
and go back to the source.
Risk Management, Controls and Substitutions of Hazardous Substances:- To
manage health and safety effectively it is important to examine workplace activities that
could cause people harm and to take appropriate precautions. This is known as “risk
management” and is a legal requirement in certain countries. The risk assessment should
identify whether a hazard is significant and the action that needs to be taken to keep the
risk to a minimum. A typical risk assessment consists of five steps : (a) Identify the
hazards, (b) Identify who might be harmed and how, (c) Evaluate the risk, check whether
the existing precautions are sufficient or further actions are needed, (d) Keep a record, (e)
Review the assessment and revise if necessary.
Having clearly evaluated and categorized the risk, action may be taken based on
either eliminating the risk altogether by some environment friendly and hazard free
substitute or controlling it so that harm is unlikely. The following principles can be applied
to control the risks :
(a) Initiation of education and training to the workers about health and safety
dangers and their risk management.
(b) Isolate chemicals from workers and isolate the storage at far way from factory
(c) Local Exhaust Ventilation (LEV), arranging proper down stream forced ventilation
for the hazardous solvents in cementing, wiping, lacquering and finishing operations.
(d) Good healthy general ventilation, this should be maintained whether hot or cold.
(e) Medical surveillance, a continuous medical surveillance to detect early signs of ill
(f) Downwards flowing of volatile and inflammable solvents with water in spray
booth cabinet .
(g) Good house keeping and canteen, proper place of eat and drink to avoid the
inhaling and touching of hazardous volatile solvents by the workers and minimize
(h) Personal Protective Equipment (PPE) and clothing like gloves for skin protection,
goggles for eye protection and specialized half-face masks with adequate filter for
respiratory protection should be supplied by the employer and used by workers at risk.
(i) Monitoring for solvents, by monitoring the air quality inside the factory in a
frequent manner by the help of Detector Tube or Solvent Monitor Badge, so that the
hazardous solvent vapours and other substances like dust etc. should not cross the
Occupational Exposure Standards (OESs) as well as the Maximum Exposure Limits
(j) Controlling fire risks, by limit quantities of solvents at work areas, limit airborne
emissions, store chemicals separately and use of fire extinguishers. Opening of
containers, transferring contents and mixing should be done in areas free from sources of
ignition even in case of static electricity discharge from a person’s body could ignite any
fumes during transfer of flammable solvents. Therefore both the container and the person
should be earthed using straps before discharge of solvents.
(k) Strict vigilance, by creating a mandatory different cell to monitor the problems and
vigilant over its risk managements and solutions.
(l) Substitutions for Hazardous Substances, Use of Water-based adhesive is an
ideal substitute to avoid the potential toxicity and flammability problems with solvents, thus
reduce the solvent hazardous. Use of hot melt adhesives are an alternative to reduce
solvents hazardous. Although there is a very low risk when polyamide types may release
amines if overheated. Use of water based finishes and binders are showing good results to
replace solvent based. Huge R&D is conducting to promote water based lacquers. Use of
TPU material in place of PVC, which is a better material in every aspect for shoe making ,
thus to avoid carcinogenetic vinyl chloride monomer, cadmium and lead stabilizer and
phthalate DEHP used as plasticizer. Use of chromium and chromium III in place of
chromium VI to avoid dermatological irritant. Use of barium-zinc would be a safer
alternatives in place of cadmium and cadmium compounds which are subject to low MELs
and can cause kidney damage with high exposure. Use of aluminium and copper in place
of nickel or to cover the nickel material in different accessories.
Conclusion :- Of course in the footwear industries the amount and magnitude of it’s
hazardous substances is quite low than some other leading industries but nevertheless it
may neglected. It’s long term health problems are of great concern. Few small initiatives as
mentioned above can change this industry more green, eco-friendly, zero hazardous
towards it’s workers and it’s consumers and can put a significant contribution towards the
fame of an industry of BETTER HUMAN HEALTH.
1. HSE publication “Controls of Substances Hazardous to Health Regulations 2002
(COSHH) PAGE 15.
2. FLIHSC publication “REACH- a guidance note for the footwear and leather
3. FLIHSC publication “Isocyanates- a guide for the footwear industry” 1998.