www.nanodiode.eu

Presentation 3:Are nanomaterials a worker health and safety risk?

Health effects identified so far

• Nanomaterials can penetrate further into the human body if inhaled and even pass into the bloodstream and travel to other organs

• Some nanomaterials (multi-walled carbon nanotubes - MWCNTs) have shown asbestos-like effects

• Lack of data available on the hazards (human and environmental) posed by nanomaterials

• Yet, we can “read across” to nanomaterials from our knowledge of effects of the same or similar materials at “bulk” size - toxicologists have not yet identified “new” health effects from nanomaterials as seen for other hazardous substances

• Toxicity can depend upon size, shape, surface charge, age, etc of the nanomaterials, so their complexity means testing for all possible variables would take many years and would be expensive

References: and images What Workers Need to Know about Nanomaterial Toxicology

https://nanohub.org/groups/gng/training_materials

Date, location

Precaution as a first response

Reference: Colvin, V.L., “The Potential Environmental Impact of Engineered Nanomaterials,” in Asmatulu, R. “Toxicity of Nanomaterials and Recent Developments in Lung Disease“ http://www.intechopen.com/books/bronchitis/toxicity-of-nanomaterials-and-recent-developments-in-lung-disease

• Given many unknowns about nanomaterial hazards, preventing worker exposure is the best approach

• Nanoparticles may enter the body through three routes: inhalation, absorption and ingestion

Date, location

Routes of exposure

INHALATION• Inhalation is the most important exposure route because it is the most

concentrated, and produces the strongest effects• Inhaled airborne nanomaterials may deposit in different parts of the lungs• Inhaled nanomaterials may travel to other organs and lymph system via

blood stream (also exposure via the olfactory bulb/nerve)

Reference:

What Workers Need to Know about Nanomaterial Toxicology

https://nanohub.org/groups/gng/training_materials

ABSORPTION• Fewer studies done on absorption than on inhalation• Studies show different results:

– little to no penetration beyond surface skin layers– Penetration of flexed, damaged or diseased skin– Penetration of intact skin within 8-24 hours

• Eyes also an exposure route• Skin studies based on short-term single applications

INGESTION• May occur after inhalation exposure when mucus is

brought up the respiratory tract and swallowed• Poor work practice can result in hand-to-mouth transfer

(e.g. eating or smoking in the work area)• Ingested nanoparticles do translocate to other organs

Date, location

Concerns about exposure

Effects from nanomaterials testing: • Cancers, including mesothelioma• Rapid and persistent pulmonary fibrosis• Cardiovascular dysfunction• Transfer to different organs (e.g. the brain, heart,

liver, intestine, lymph system) – via the olfactory nerve into the brain, via the lungs, via the skin

• Affect cells: their shape and structure, damage cell membranes

• Irritation responses (e.g. respiratory problems)• DNA and liver damage

Reference:: What Workers Need to Know about Nanomaterial Toxicology

https://nanohub.org/groups/gng/training_materials

Images:

http://science.howstuffworks.com/nanotechnology5.htm

General Safe Practices for Working with Engineered Nanomaterials in Research Laboratories (http://www.cdc.gov/niosh/docs/2012-147/pdfs/2012-147.pdf)

Date, location

Reactivity at nanoscale

• Nanomaterials have much larger surface areas than the same mass of “bulk” materials so a greater amount of the material can come into contact with surrounding materials, increasing reactivity

• E.g. A solid cube of a material 1 cm³ has 6cm² of surface area = about equal to one side of half a stick of gum. The same 1cm³ cube filled with 1 nanometre-sized cubes (each with an area of 6 nanometres²) = 6,000 square metres = a bit larger than a 4-lane Olympic sized swimming pool

• Their higher reactivity levels make nanomaterials attractive for introduction into products and production processes (new functions, increased energy efficiency) but this reactivity also applies to biological processes (the body) and we know that nanomaterials can travel further into the body via inhalation

Reference and image:

http://www.nano.gov/nanotech-101/special

Date, location

Risks from presence of nanomaterials

Reference and image: DG Employment, 2014, Guidance on the protection of the health and safety of workers from the potential risks related to nanomaterials at work: Guidance for employers and health and safety practitioners

• This table shows a summary of the risks to be assessed under EU chemicals-related occupational health and safety legislation, and some risk factors related to hazardous chemicals

• In red are the risk factors that need to be given particular attention when doing a risk assessment of the nanomaterial/s in the workplace

Risk Some risk factorsRisks due to inhalation of the agent Toxicity of the nanomaterial

Physicochemical characteristics of the nanomaterial Environmental concentration Exposure time Particularly sensitive workers Inappropriate selection and/or use of RPE

Risks due to absorption through the skin Location and extent of the contact with the skin Toxicity of the nanomaterial via the skin Duration and frequency of contact Particularly sensitive workers Inappropriate selection and/or use of RPE

Risks due to contact with the skin or eyes Inappropriate selection and/or use of RPE Inappropriate work procedure Incorrect transfer procedure

Risks due to ingestion Toxicity of the nanomaterial Potential toxicity of the nanomaterial Incorrect personal hygiene habits Possibility of eating, drinking or smoking in the workplace Particularly sensitive workers

Risks of fire and/or explosion Physical state (ultrafine dust) Pressure/temperature Flammability/calorific value Airborne concentration Sources of ignition

Risks due to hazardous chemical reactions Chemical reactivity and instability of hazardous chemical agents Inadequate cooling systems Unreliable system for controlling key variables in the reaction

(pressure, temperature and flow control)

Risks arising from installations which may have consequences on the health and safety of workers

Corrosion of materials and installations Deficient or non-existent facilities for controlling leaks and spills

(retaining trays, protection against mechanical impacts) Deficient or non-existent preventive maintenance

Date, location

Potential worker exposure across product lifecycle

• Worker exposure can occur across the lifecycle of a nano-enabled product: from nanomaterial production, to manufacturing of a nano-enabled product, to the product’s use (e.g. machining of the product), and in its end-of-life management (recycling or incineration/disposal)

• Of all these phases, nanomaterial production workplaces are the most “assessed” for worker exposure

Image:

http://www.nanotortlaw.com/2013/08/12/nanoparticle-waste-treatment-concerns-evaluated-in-a-new-study/

Date, location