RECENT TOXICOLOGICAL ISSUES

(updated 05/12/14)

 

 

SKIN SENSITIZERS AND IRRITANTS:  

 The following document addresses our use of a quantitative risk assessment approach for evaluating skin sensitizers and irritants for which human patch test results are available. Two examples of such an approach are the risk assessment for isothiazolinones and formaldehyde-releasing preservatives.

 

 

 QUANTITATIVE ASSESSMENT OF SKIN ALLERGENS:

Acceptable levels of allergens have been determined by the percentage of the allergen that can be used without resulting in an allergic reaction. Human insult patch testing has shown that the risk of an allergic reaction is related to the amount of allergen that comes into contact with the skin surface. This new approach to the quantitative assessment of allergens is detailed in the following paper.

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LEAD IN CONSUMER PRODUCTS: 

New state and federal regulations require that lead levels in children's products meet certain standards. Current test methods for determining total lead may determine values that erroneously low because of plastic matrix effects. This paper identifies methods that can accurately detect total lead levels in plastics.

 

Lead is found in all ball point pen tips above the total lead levels specified in a new consumer safety law (CPSIA). A new study addresses whether or not exposure and absorption of lead in such tips can occur.

 

MERCURY:

Mercury is found ubiquitously in foods. This paper identifies expected mercury levels in various food groups and the results of analysis of mercury in high fructose corn syrups.

 

BIOACCESSIBILITY TESTING: 

A number of studies of lead-containing materials have been conducted to support the use of bioaccessibility testing as means for determining chronic risk from metals contained in ingested materials. The following papers summarize these studies. The first paper compares the results of feeding studies of lead-containing ores with bioaccessibility testing of these ores. the second paper addresses a mass ion effect seen when there is an excess extractant volume is used for testing.

CERAMIC GLAZE EXPOSURES:

Contemporary ceramic studios offer a venue for ceramic decorating to both children and adults. Although decorating is done with lead-free glazes, completed pieces are usually dipped in a leaded-glaze and fired. A study of several contemporary ceramic studios has shown the potential for lead exposure to both workers and patrons that can be controlled with change in practices.

Connecticut recently found that leaded glazes were being used in school systems even below the high school level. This paper gives details of lead exposures in 13 schools and 18 art rooms where lead contamination occurred.

Lead exposures in ceramic studios can be monitored by wipe testing. EPA has set an acceptable level of 40 micrograms/m2 for children. But, as seen in this paper, an acceptable exposure level for adults may be much higher.

Recommendations for safe work practices in a ceramic studio can be found here.

A study has recently been completed to determine the magnitude of hand contamination and hand to mouth transfer with intensive ceramic decorating activities by finger, sponge or brush. A copy of this research report can be found here.

A number of ceramic glazes use metal-based stains as colorants. Their potential for skin absorption relates to their solubility. A summary of skin absorption studies of soluble metals can be found here.

BORIC ACID RISK ASSESSMENT:

Soluble boron, in the form of boric acid, can cause acute brain damage and/or seizures with ingestion of large amounts over short periods of time. With chronic exposures there is a risk of fetal toxicity and testicular effects with decreased fertility. This risk assessment evaluates new knowledge on the toxicity of boron with a focus on chronic developmental and reproductive toxicity.

Manganese is a neurotoxin with a parkinsonian syndrome found in individuals exposed to high levels of fumes from ferromanganese ores. Neuropsychological changes can be found at lower exposures. A critical review of the literature on this subject can be found at http://www.aws.org/duke_study/index.html.

Canada's Consumer Chemical and Containers Regulations, 2001, specifies that products containing >10% low viscosity compounds (certain hydrocarbons, alcohols and ketones that present aspiration risks) must have child-resistant packaging except " a spray container that cannot be opened and that disperses the product as a mist." This research report describes the development of a test method to determine whether or not an aerosol spray is a mist and reports on tests of a wide variety of aerosol products.

Spontaneous combustion: rags soaked with linseed oil present a risk of spontaneous combustion. In the last 2 decades, a number of oils have been developed to substitute for or amend linseed oil including safflower oil an walnut oil. ASTM has developed method D6801 to test for spontaneous combustion risk. This method was initially used to evaluate linseed oil-based products but now has been extended the evaluation of a wide variety of oils and products, including those used in the art material field, wood refinishing and foods. A report of these expanded tests can be found here.

 

Pepper Spray Article: Dr. Woodhall Stopford MD, MSPH and C. Gregory Smith MD, MSPH

COPPER RISK ASSESSMENT:

 Acute exposures to soluble copper have been associated with hemolysis of red blood cells and acute kidney failure while chronic exposures have been associated with cirrhosis of the liver. Copper can cause effects when inhaled. This copper risk assessment will be useful in determining acceptable levels of respirable copper and soluble copper in art and craft materials.

Titanium dioxide is a white pigment widely used in art materials.  An assessment of the potential of exposures to titanium dioxide to be associated with a risk of lung tumors in man has been submitted to the California's Office of Environmental Health Hazard Assessment, as follows:  Titanium Dioxide Risk

There has been a recent concern about whether or not excessive exposure to phthalate esters can occur from using polymer clay. This study investigates hand contamination when using polymer clay, both in the laboratory and by professional polymer clay artists, and addresses the potential for incidental ingestion of phthalate esters associated with hand contamination.  Polymer Clay Study

We have completed a number of studies to measure aerosol production during various art and craft activities. The following report details these studies and uses them to model aerosol exposures associated with these activities.  Aerosol Exposure Report

 

California's OEHHA has recently proposed a inhalation reference exposure level (iREL) for crystalline silica of 3 micrograms/m3 for a particle distribution with a mass median aerodynamic diameter (MMAD) of 10 microns or less. Particles with a low MMAD (4 microns or less) can readily get deep into the lung where larger particles deposit in the nose. The basis for their proposed iREL are studies where exposures were characterized to respirable crystalline silica particles with a distrubtion with a MMAD of 4 micons. Most environmental exposures to crystalline silica occur from natural sources where quartz particles predominate in the larger sized dust fractions. Choosing a MMAD of <10 microns for this iREL will increase the apparent crystalline silica exposure levels by as much as an order a magnitude above levels that would reflect exposures within the the respirable range on which your iREL is based. The attached paper gives the basis for using a MMAD of 4 microns or less for Californias crystalline silica iREL.   OEHHA Quartz Response

 

SOLUBLE COPPER:

ATSDR has proposed a minimum risk level (MRL) for soluble copper based upon a concentration-dependent effect, nausea. This comment recommends that a dose-related effect be used to determine copper’s MRL, liver toxicity.   Copper MRL

 

SOLUBLE COBALT:

Soluble cobalt: ATSDR has proposed a minimum risk level (MRL) for soluble cobalt based upon a therapeutic effect, increases in hemoglobin. This comment recommends that toxicity-related endpoints, cardiomyopathy and thyroid dysfunction, be used to determine the MRL. A risk assessment based on this approach has been published at:

Brock T, Stopford W. Bioaccessibility of metals in human health risk assessment: Evaluating risk from exposure to cobalt compounds. J Environ Management. 2003; 3(5):71N-76N

A paper where we evaluate the bioaccessibility (solubility) of cobalt compounds using various media, including synthetic intestinal juice, can be found at:

Stopford W, Turner J, Cappellini D, Brock T. Bioaccessibility testing of cobalt compounds. J Environ Management. 2003; 3(5):675-680.

 

 

 

Guidelines for safe use of ceramics: attached is a copy of the proposed appendix to ASTM's D1023: Guidelines for the Safe Use of Ceramic Art Materials.     Ceramic Appendix

 

Risks associated with work with solvent-based markers: two studies have been completed that look at solvent exposures to users of solvent-based markers.

One study looked at xylene exposure from professional use of xylene-based markers by graphic artists. This study found that the maximum exposure to xylene averaged 0.5 ppm, even when use was for as much as 210 minutes a day or an average of 102 minutes a day.  Graphic Artist Study

A second study looked at solvent exposure from simulated classroom activities involving solvent-based whiteboard markers. Exposures projected to 25 users working simultaneously in a poorly ventilated classroom showed low exposures.   Whiteboard Marker Study

 

RISKS ASSOCIATED WITH EXPOSURE TO DUSTS AND AEROSOLS:

  A number of studies have been completed to address whether or not use of art materials is associated with generation of respirable dusts at levels that may lead to ill health. These studies include:

·         the evaluation of dusts produced from the use and clean up of art works made with pastels and chalks  Pastel Report

·         The evaluation of respirable dusts generated during a number of art and craft activities, including working with clays and slips and associated cleanup activities and the evaluation of aerosols generated during the spray application of water paints, gessos, acrylic paints and glazes. These studies are summarized in a report to CPSC on risks of talc exposure associated with art and craft activities CPSC Report

 

PHTHALATES IN POLYMER CLAYS:

The National Toxicology Program (NTP) has recently completed a re-assessment of the hazards associated with exposure to some phthalate esters. Some of these phthalate esters are used as plasticizers in polymer clays. Polymer clays are modeling clays that are heat set at a low temperature. ACMI's risk assessment of hazards associated with the use and curing of these clays includes NTP findings as well as test information for the potential for phthalates to be released during curing. ACMI's detailed risk assessment is in the following Word file, polymerclays1.doc. For a summary of this assessment see polymerclaysummary.doc.

ASBESTIFORM FIBERS IN CRAYONS:

Concern has been raised because of the finding of  asbestiform fibers that are chemically transitional between asbestos and talc in talcs used to make crayons. For information on this issue see http://www.acminet.org. For CPSC’s position paper on asbestos fibers in crayons Email CPSC at altzman@cpsc.gov. The Research Triangle Institute has reviewed current methods for analyzing asbestiform fibers in talc or talc-containing products.  An executive summary of their evaluation can be found at http://www.rti.org/publications/pubs.cfm?pub_cat_id=20.(See Asbestos Analysis). A critique of the RTI evaluation has been provided by the RJ Lee Group.  This critique can be found in the attached file: RTI critique.   Dr. Woodhall Stopford's comments concerning the National Toxicology Program's consideration of listing of talc as a carcinogen can be found in the following file: Stopford talc comments

 

BENZOISOTHIAZOLINONE ACTION LEVEL:

The action level for benzisothiazolinone, a preservative, has been decreased to 470 ppm in art materials based on human testing showing irritation and sensitization potential at higher levels.

 

NATURAL RUBBER LATEX:

 ACMI now requires labeling for natural rubber latex sensitization hazards in all liquid products containing natural rubber latex and in artists rubber erasers containing natural rubber latex. Recent studies have shown extractable rubber latex antigen in this type of eraser. Studies are ongoing looking for extractable rubber latex antigen in erasers containing <10% natural rubber latex.

 

COPPER DUST:

A recent report from the National Poison Control Center Network identified a death in a senior citizen who inhaled copper dust while working with a craft project at a day care center for senior citizens. ACMI’s Toxicology Advisory Board has reviewed this issue and agrees that brass or bronze powders should be tested for respirable size as a measure of risk of inhalation.

 

ACID YELLOW 42:

ACMI requires chronic health hazard labeling for this dye because it can be metabolized in the gut to benzidine. This dye has now been sulfonated and the sulfonated product has been shown not to be metabolizable to benzidine.


 

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