Looking After Our Health in the Studio

Hello everyone! In this post, I want to focus on a subject that is very important to us as ceramic artists.

Looking after our health in a ceramic studio is essential. Make no mistake: in ceramics, we work directly with various toxic substances that often affect our bodies slowly and silently.

Ceramic practice requires attention to the risks of exposure to dust and other hazardous substances. We cannot afford to be careless: we need to identify these risks and take measures to reduce and control exposure, without assuming that a few precautions eliminate every hazard.

Before using raw materials or glazes, ask the supplier for the safety data sheet (SDS) and check the information on composition, hazards, handling and protection. The absence of a warning on the packaging does not demonstrate that a product is harmless.

Main Hazards in a Ceramic Studio

Toxic Exposure

Many glaze raw materials contain hazardous substances. Exposure routes and effects depend on the composition and task; they may include inhalation, ingestion and skin contact. Keep food and drink out of the work area, wash your hands and keep work clothing separate from clothing used at home. Select gloves and other protective equipment according to the SDS and risk assessment.

Symptoms of poisoning can vary greatly depending on the substance involved. If you suspect poisoning, contact your doctor urgently for treatment.

Respiratory protection must be selected according to the contaminant, concentration and task, with competent guidance. P3 filters are intended for particles and do not, on their own, protect against gases and vapours. Tight-fitting respirators require face-fit testing and a seal check at each use. Surgical masks are not a substitute for this protection. Follow the manufacturer's instructions for maintenance and storage in a clean place; a respirator does not replace dust control at source.

Silicosis

Silicosis is a serious, irreversible lung disease caused by inhaling respirable crystalline silica. Risk depends on exposure, which may occur during tasks involving clays and other raw materials containing this form of silica. Respirable particles may be invisible to the naked eye. Harm may become apparent after years of exposure, while intense exposure can cause disease more rapidly. Exposure to respirable crystalline silica is also associated with lung cancer.

Keeping clay damp helps reduce dust generation, but does not make the material universally harmless. When clay residues dry and become dispersed, they may generate respirable dust; the presence of crystalline silica and other hazards depends on the raw material.

Avoid dry sweeping and using compressed air to clean dust. Prefer wet methods or industrial vacuum equipment suitable for hazardous dust, with classification and filtration selected according to the risk assessment; domestic vacuum cleaners must not be assumed suitable. Prevent wet residues from drying on surfaces. General ventilation does not replace local exhaust ventilation where needed. For sanding and glaze spraying, assess the need for enclosure, extraction at source and suitable respiratory protection.

Injuries

We work with fire, so we need to protect ourselves from burns. Wear suitable gloves when handling hot objects. Do not touch kilns while they are operating: their surfaces can be very hot.

Wear gloves when removing pieces from the kiln, even when it is cold. Pieces may be brittle and can cut your hands. Ceramics can cut just like knives!

Looking inside a hot kiln requires eye protection selected for the radiation and task conditions. Follow guidance from the kiln manufacturer and a competent professional on filter type and protective shade. Do not assume that a fixed temperature threshold or just any welding goggles provide suitable protection. Sunglasses are not a substitute for task-specific protection.

Materials and Their Toxicity:

Below is a general list I have put together of materials commonly used by ceramic artists and their relationship to health:

• Clays, kaolin, ball clay and slips must not be considered safe to ingest. Kaolinite is a mineral distinct from free crystalline silica; commercial raw materials may contain quartz and other impurities. Kaolin dust also requires control: consult the SDS and product composition rather than exempting it from protective precautions.
• Feldspar, nepheline syenite and albite are silicate minerals, whereas calcium carbonate and dolomite are carbonates. Silica bound within a silicate structure must not be confused with free crystalline silica. Check each raw material's SDS for quartz or other impurities and dust hazards.
• Barium carbonate is toxic and must be handled with care.
• Talc and wollastonite may produce toxic dust, as the particles are fibrous. Take care.
• Lead oxide, lead carbonate, red lead, cadmium, selenium and similar materials should only be handled by specialists.
• Frits must not be considered universally inert or harmless. Their composition and dust exposure hazards vary; consult the SDS, particularly where lead or other hazardous constituents are present.
• Some substances are inert when cold but become hazardous when they volatilise in the kiln. Dust from volatilised material that settles around the kiln also presents a risk of poisoning. Pay particular attention to colouring metal oxides, such as manganese, cobalt, nickel, chromium and vanadium.

Ceramics Free from Toxic Substances

If you make functional ceramics, another question to ask yourself is: are my pieces free from toxic substances? Remember that your customers will use your products to serve food and drinks, and the pieces must not pose a risk to their health.

If you are buying a glaze and do not know its composition, ask the supplier about its toxicity. Give preference to lead-free glazes. If you make your own glazes, check the composition and toxicity of each ingredient before using it.

Assistance

For current information on poison assistance in Brazil, consult Anvisa's official Disque-Intoxicação page and the contact details of centres in your region. The page consulted lists the toll-free number 0800-722-6001. The historical record reproduced below must not be used as an up-to-date directory of centres.

Historical record: the quotation below was consulted on 17 November 2018 at the former address http://portal.anvisa.gov.br/renaciat. Its centre counts and administrative description belong to that record; they do not represent verification of the network's current structure.

“Renaciat, coordinated by Anvisa, was established in 2005 under RDC No. 19. It comprises 36 Poison Information and Assistance Centres (Ciats), operating in university hospitals, state and municipal health departments, and foundations across 19 Brazilian states and federal units.
The Ciats aim to provide toxicological information, as well as diagnosis, treatment and case recording for poisoning caused by pesticides, medicines, cosmetics, household cleaning products, industrial chemicals, metals, toxic plants, venomous animals and any other substances potentially harmful to human beings.

The centres maintain a 24-hour service to respond to enquiries about poisoning by telephone and through hospital services in Brazil's Unified Health System (SUS). Emergency and urgent assistance is provided to health professionals who need information or guidance to manage cases, and to the general public.

The Disque-Intoxicação poison helpline can be reached on 0800-722-6001. Calls are free and are answered by one of the 36 units of the National Network of Poison Information and Assistance Centres (Renaciat). The call is transferred to the Ciat nearest the caller's region. The 36 centres are equipped to receive long-distance calls 24 hours a day, seven days a week, throughout the year.”

That's all, everyone! Take care, and see you next time!

Sources:

• Renaciat. http://portal.anvisa.gov.br/renaciat. Accessed on 17 November 2018.
• Being Realistic About Toxicity and Safety in Ceramics. https://digitalfire.com/4sight/education/being_realistic_about_toxicity_and_safety_in_ceramics_278.html. Accessed on 17 November 2018.
• HSE — Glaze and colour preparation (CR1)
• HSE — Spraying glazes and colours (CR5)
• HSE — Fit testing basics
• NIOSH — Kaolin
• OSHA — Eye and face protection (1910.133)
• Anvisa — Disque-Intoxicação