Health and Safety ReportVolume 4, Issue 8 - August 2006

Titanium dioxide has recently been classified by the International Agency for Research on Cancer (IARC) as an IARC Group 2B carcinogen '' possibly carcinogen to humans''. Titanium dioxide accounts for 70% of the total production volume of pigments worldwide. It is widely used to provide whiteness and opacity to products such as paints, plastics, papers, inks, foods, and toothpastes. It is also used in cosmetic and skin care products, and it is present in almost every sunblock, where it helps protect the skin from ultraviolet light.

With such widespread use of titanium dioxide, it is important to understand that the IARC conclusions are based on very specific evidence. This evidence showed that high concentrations of pigment-grade (powdered) and ultrafine titanium dioxide dust caused respiratory tract cancer in rats exposed by inhalation and intratracheal instillation*. The series of biological events or steps that produce the rat lung cancers (e.g. particle deposition, impaired lung clearance, cell injury, fibrosis, mutations and ultimately cancer) have also been seen in people working in dusty environments. Therefore, the observations of cancer in animals were considered, by IARC, as relevant to people doing jobs with exposures to titanium dioxide dust. For example, titanium dioxide production workers may be exposed to high dust concentrations during packing, milling, site cleaning and maintenance, if there are insufficient dust control measures in place. However, it should be noted that the human studies conducted so far do not suggest an association between occupational exposure to titanium dioxide and an increased risk for cancer.

The Workplace Hazardous Materials Information System (WHMIS) is Canada's hazard communication standard. The WHMIS Controlled Products Regulations require that chemicals, listed in Group 1 or Group 2 in the IARC Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans, be classified under WHMIS Class D2A (carcinogenic). The classification decision on titanium dioxide has been published on the IARC website and in a summary article published in The Lancet.

Representatives from Health Canada (National Office of WHMIS) recently consulted with the Quebec CSST and CCOHS (the two main agencies providing WHMIS classifications to the public) regarding the implications of the IARC decision to the WHMIS classification of titanium dioxide. It was agreed that titanium dioxide does now meet the criteria for WHMIS D2A (carcinogen) based on the information released by IARC to date, and that it is not necessary to wait for release of the full monograph.

Manufacturers and suppliers of titanium dioxide are advised to review and update their material safety data sheets and product labels based on this new information as soon as possible. Employers should review their occupational hygiene programs to ensure that exposure to titanium dioxide dust is eliminated or reduced to the minimum possible. Workers should be educated concerning this potential newly recognized risk to their health and trained in proper work procedures.

* Intratracheal administration is an exposure procedure that introduces the material directly into the lungs via the trachea, bypassing protective mechanisms in the respiratory system.

More information:

International Agency for Research on Cancer (IARC): Titanium dioxide (IARC Group 2B), Summary of reported data, Feb. 2006



Explanation of the IARC evaluations



Health Canada: Hazard-specific issues - substances assessed for carcinogenicity



Baan, R., et al. Carcinogenicity of carbon black, titanium dioxide, and talc. The Lancet Oncology. Vol. 7 (Apr. 2006). P. 295-296

You can find more information with CCOHS' CHEMINFO.

A few years ago, three construction employees in North Carolina were taking a lunch break in the shade of a concrete tilt-up wall panel. The 20-tonne, 23-foot-high, 20-foot-wide wall was inadequately supported and fell on the employees, killing all three.

Another fatality occurred closer to home, early this summer. A carpenter in Saint John was killed at his Dieppe, NB worksite when a concrete wall fell over on him. The wall weighed more than 27 tonnes. Workplace health and safety officials and the coroner's office are investigating the incident.

"Tilt-up" construction, as defined by the Cement Association of Canada, is a quick, economical method of constructing concrete walls. Wall panels are cast horizontally on the floor slab. Then, once they are strong enough, a mobile crane lifts the panels up and sets them on a foundation. The panels are temporarily braced while the roof and upper floor framing is constructed. Tilt-up concrete is most commonly used for one to three story buildings, and according to the Tilt Up Concrete Association (TUCA) it a preferred method of construction for many types of buildings. There are risks and hazards that must be considered to ensure that people have the information, tools and abilities to work safely in this fast growing industry.

An investigation of the incident in North Carolina revealed that the employer had failed to install adequate bracing, and/or had removed temporary braces on several of the tilt-up wall panels before completing all permanent connections to the structure. Not all joist welds, grout, and pour back strips - a requirement in the contract documents - were in place before the temporary braces were removed. Several "K" series steel joists, designed to be attached to the embed plates, were not welded or properly secured. Furthermore, neither the supervisors nor the employees had the knowledge and training necessary to work safely and address hazards associated with tilt-up construction

Following the North Carolina fatalities, the Occupational Safety and Health Administration (OSHA) issued a Safety and Health Information Bulletin to assist employers in providing a safe and healthy workplace.

The bulletin recommends that employers take the following safety measures:

• Maintain programs to provide frequent inspections of the job site, materials, and equipment, by designated, competent persons;


• Ensure each employee is familiar with regulations applicable to their work environment, and trained in how to recognize and avoid unsafe conditions. (For example, employers should instruct supervisors and workers not to remove temporary braces until roof structure and/or columns are in place to stabilize the building.)


• Comply with all requirements for pre-cast concrete construction;


• Ensure that tilt-up panels are properly braced to resist wind and lateral forces;


• Use only certified welders when welding steel joists to embed on tilt-up wall panels.

Employee assistance programs (EAPs) originated in the 1940s, to fill a need for confidential, short term counselling for employees experiencing personal problems. Today, many of Canada's employers purchase EAP services and make them available to employees and their immediate family members.

The purpose of an EAP is to provide confidential, accessible services to help people resolve issues that may be affecting their work, whether or not these problems stem from the workplace. EAP service providers counsel employees on a number of issues, which may include those of a personal nature, job stress, relationships, eldercare, childcare, parenting, harassment, substance abuse, separation and loss, balancing work and family, financial or legal issues, and family violence.

In most cases, staff members have easy access to the EAP phone number. Should the need arise, the employee can privately call the number provided by the employer and immediately contact a referring agent, who will refer the employee to the appropriate professional. Depending on the nature or severity of the problem, the referral agent will determine whether the employee should be referred to a professional within the EAP or to an outside resource (such as a substance abuse program).

While many employees call the EAP voluntarily, others are sometimes prompted to do so by a concerned supervisor, friend or co-worker. No record of these informal referrals will appear in the employee's personnel file.

When a supervisor makes a formal referral, recommending that the employee consult the EAP because his or her job performance may be suffering, the employer may or may not decide to make a note of the referral in the employee's file. In either case, however, what is discussed between the employee and the counsellor during their private sessions remains confidential and will never be reported to the employer.

Choosing an EAP

EAPs come in different shapes and sizes, and don't all offer the same services. If you are shopping around for an EAP for your organization, here are some important questions to ask a prospective EAP:

• How long the company has been operating? Ask for a list of references.


• Does the EAP have offices in your area?


• Which services do they provide, and how exactly do employees access those services
?

• How long does the EAP take to call back an employee (preferably within 24 or 48 hours)
.

• You will also want to know how the EAP determines which employees need what kinds of referrals, and whether the EAP's list of referral sources is up-to-date.


• How many EAP staff members do they have, and do they intend to be available outside the typical 9 to 5 business hours? Find out the credentials of those counsellors too - education, training, and years of experience.


• How do they promote their services to employees?


• What types of reports they can generate for employers?


• What the service will cost your organization?

In July 2006, the Food and Agriculture Organization of the United Nations (FAO), the World Organization for Animal Health (OIE) and the World Health Organization (WHO) launched a global early warning system for animal diseases transmissible to humans (zoonoses). This Global Early Warning and Response System (GLEWS) is the first of its kind, aimed at predicting and responding to animal diseases, including zoonoses, worldwide.

Failure to detect and respond to animal diseases at the early stage, and the inability to control major diseases at their source, have contributed to the spread of diseases of animal origin across borders. These diseases include bovine spongiform encephalopathy (BSE), Severe Acute Respiratory Syndrome (SARS), foot-and-mouth disease (FMD), classical swine fever (CSF) and avian influenza.

The new GLEWS system aims to provide better prediction and prevention of animal disease threats through the sharing of information, epidemiological analysis and joint field missions to assess and control outbreaks in animals and humans. History demonstrates that early and accurate detection of new outbreaks of epidemic livestock diseases, and the ability to predict their spread is essential to containing and controlling them.

"Today, the spread of avian flu reinforces the fact that the animal and human health sectors must work closely together, and that early detection and coordination is critical," says Susanne Weber-Mosdorf, WHO Assistant Director-General. "This new network is an important step forward."

Using the GLEWS web-based electronic platform, partner organizations will share their tracking and verification channels to jointly analyse data and decide whether to issue common early warning messages. These alert messages will describe the possible implications of disease spread among animals at national, regional and international levels, and its potential impact on public health.

Eventually, the system should improve the quality and accuracy of information disseminated on zoonoses. Joining efforts of all partners is expected to enhance analytical capabilities and global, risk-based surveillance to determine where trans-boundary animal diseases occur - with the ultimate goal of containing and controlling the diseases.

The system's success will depend heavily on the quality of information collected at the grass-roots level as well as on the ability of national veterinary authorities to report disease occurrence in a structured and timely manner and share information at all levels.

Dr. Bernard Vallat, Director General of the OIE, commented, "From an animal health point of view, controlling contagious animal diseases in their early stages is easier and less expensive for the international community. In cases of zoonoses, this system will enable control measures that can also benefit public health."

More on zoonoses from the World Health Organization (WHO)


Read the media release from the Food and Agriculture Organization of the United Nations

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