The Forestry Forum

Hi there

I have been doing  research on toxic woods and I havn't really found what I am looking for ??? ::) ???.

Any information you have to share would be great 8)

Not sure if I can give you a good enough answer.  However, it is my understanding that most cedar is toxic when doing wood turning.

Walnut, butternut, cherry and most south American hardwoods.  But, it depends on the type of toxicity and on what is it toxic.

Welcome to the Forestry Forum, Emah.

What is it that you are looking for?

Most woods have some toxicity.  Some have very little and some are filled.  It also matters what the toxins affect.  Poison Ivy affects humans, Black walnut affects other vegetation and horses, cedar causes respiratory problems, Holly (Florida, Dahoon and Yaupon) is a purgative

Tom's right. Also, many people have an allergic reaction to sawdust from nut trees.

Here's a link that has a lot of info:
Veterinary Medicine Library Toxic Plants Database (http://www.library.uiuc.edu/vex/toxic/comlist.htm)

It may look comprehensive but it is not. For example: The bark of black locust is toxic to cattle but black locust is not on the list.  Poison sumac wasn't on the list but I don't think it's going to show up at the mill. ;D

I've probably have more links if I could just find them. smiley_headscratch

Edit to add more lists.

Here's another:Toxic Plants by Degree of Toxicity (http://www.vet.purdue.edu/depts/addl/toxic/bytox1.htm)
Again, not complete.

You can do a net search for 'toxic plants' and pull up dozens of lists.

Here's another:
Potentially Toxic Woods (http://www.mimf.com/archives/toxic.htm)

Got that with a net search for 'toxic wood'  ;D

Emah
It is seems so easy to take scattered information, like pertaining to what is "toxic" and what isn't, and without tests and verification, make it seem more important and true by placing it in a "detailed web page".   References to the gleaned information would be good.

Like Tom said, different people react differently to different woods. I recall hearing about Silky Oak, and it caused some woodworkers to have severe reactions, while others could work with it and have no problems at all.
I get a reaction around fiberglass. Is it then toxic?

And what is "toxic"? 

Just mention this for discussion, not to suggest you don't have a web page about it.  :)

like beenthere said what is toxic?  and if I remember RIGHT (wich is highly doubtful most of the time as I keep getting told I have memory failure problems, funny thing is it is usually the woman telling me I forgot to do something she told me to do ;) )

anyhow TOXIC by definition means that it all depends on the level of exposure and the critter being exposed to the toxin.   all spiders are toxic but only a few are "poisonous" to people where as they are mostly all "poisonous" to bugs.   the term TOXIC means that it will become hazardous or possibly "poisonous" (generally to humans) at a certain LEVEL of exposure.   Anyone know about "MSG" mono-sodium-glutimate, which is a food additive found in LOTS of food as a flavor enhancer.   it tastes good but is actually a toxin some poeople can eat it raw concentrated others it is just alittle bit to cause nausea vomiting ect.  (my ex was very acceptable to it is how I found this out.)

ANYHOW now talking woods I have heard that APPLE contains a high level of ARSENIC poisen in the seeds and in the wood so smoking burning it could cause problems but I'm not 100% sure of it's actual levels and may be a environmental factors which can add to the arsenic levels in the woods.  also heard that Red cedar toxic for small animals (oil acts like poison ivy or oak does to people.)

mark M

I know certain taxus will kill cattle. I saw it first hand and it wasn't pretty. That's why I had the 1st link I posted but I don't think taxus is listed in it. I don't know if any of the taxus grow big enough to show up in woodworking except perhaps as wood turnings.

Q. falcata var pagodifolia a subspecies of southern red called Cherrybark oak , which grows bigger and has a much better form. Decomposing leaves release salicylic acid, an allelopathogen.

CCA treated lumber is pretty toxic ;D....Sorry...couldn't resist :D

Allergies

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Jonathan: There are probably more people allergic to their wife than wood.
Here is some interesting info for you. As it says maybe 2% to 5% of people may be allergic to "a" wood.

Health Concerns
Wood jewelry is one of the most comfortable and grounding materials we have available to us. With the ever increasing amount of suppliers trying to break into the wood jewelry market, it has become a necessity to supply the industry with this helpful guide to safer wood products. While most of the research available to woodworkers is a good starting point, it was not designed as a guide to wearable woods. The problem being is that the research is specific to wood dust and not the actual skin contact with wood. Wood dust produces an extremely large amount of surface area, which has the potential produce much more extreme reactions than exposure to the amount of surface area that is in contact with the skin in the case of wearable wood.
Only 2% to 5% of the population will develop an allergic sensitivity to one or more compounds found in wood. Contact dermatitis from timbers is usually attributable to contamination of the skin during machining. Handling of solid wood rarely induces dermatitis, however any species that contains quinones, especially Dalbergia species, may do so. (Calnan 1972). 1
After lengthy research we have put together this guide to help educate both you the wearer and hopefully some of the manufacturers producing potentially dangerous products.
Interestingly, most research seems to be reported based on only a few case studies, many of which go back up to 100 years and these results are not obtained by clinical studies with large sample groups. However, these isolated cases should not be dismissed; they are very interesting in showing patterns of cross-sensitivities, and many have been accompanied by positive patch tests from extracts of the offending compounds.
"The structural components of wood are cellulose, hemicellulose, and lignin, but it is the accessory substances or "extractives" found mainly in the heartwood that are responsible for most toxic effects. Vorreiter (1949/1958 ) classifies these as follows: (1) fats, resins, oils, and waxes ; (2) proteins, gums, latex, mucus, starch, and sugers ; (3) alkaloids, bitter principles, dyes, tannins, glycosides, camphor, perfumes, etc.; (4) inorganic and organic acids and salts ; (5) minerals." 1
"Some of these act as food reserves for latent growth periods, some as hardening agents, and others protect against mechanical injuries or attack by bacteria, fungi, insects and larger animals (Dietrichs, 1958). Some are metabolic by-products or end-products of no apparent use to the tree." 1

Toxic Substances
Quinones
The culprit behind these allergies is a group of chemicals called quinones, naturally occurring compounds, often used to make dyes. The quinones are produced as defensive agents against fungal and predator attacks (including me, the woodworker and you, the collector). Quinones play a major role in allergic contact dermatitis caused by plants.
The primary allergens are benzoquinones or naphthoquinones but also compounds, such as catechols, coumarins, and other phenolic or flavonoid compounds, which are bioconverted into ortho-quinones or para-quinones. Catechol is a main constituent of urushiol, which is the allergen in poison ivy. 2
It is possible that once sensitized to one of these quinones that cross reactions to similar quinones and/or structures can develop. Included at the bottom of this page is a list of some of the more popular woods that are not suitable to wear.




Other compounds
Some of the other compounds that are known to cause harmful responses include: alkaloids and glycosides (systemic effects, pharmacological rather than allergic), saponins (effective through broken skin only), phenols (the strongest skin-sensitizers, especially the catechols of the poison-ivy family), stilbenes (which occur in allergenic woods, but only chlorophorin and coniferyl benzoate are known to sensitize), terpenes (including delta-3-carene from turpentine, sesquiterpene lactones and other sensitizing liverworts found on bark, and euphorbol and other complex terpenes on uncertain toxicity found in the latex of Euphorbiaceae), furocoumarins (photosensitizing and may be partly responsible for skin reactions but has yet to be proved), and dalbergiones (severe skin irritants).

Toxicity
The hazardous forms that may give rise to health risks are:
"The main effect is irritation. An irritant is something that can cause inflammation or irritation. This can be caused by skin contact with the wood, its dust, its bark, its sap, or even lichens growing on the bark. Irritation can, in some species of wood, lead to nettle rashes or irritant dermatitis. These effects tend to appear on the forearm, backs of the hands, the face (particularly eyelids) neck, scalp and the genitals. On average, they take 15 days to develop, but have been known to occur in a few hours to many months. Symptoms usually only persist as long as the affected skin site remains in contact with the source of irritation. Symptoms subside when contact with the irritant is removed.
Sensitization dermatitis is more problematic and is usually caused by skin exposure to fine wood dust of certain species. Sensitization is an allergic reaction to a substance which is usually irreversible. Resulting in hypersensitivity and susceptibity to being overly responsive. This is also referred to as allergic contact dermatitis and results in similar skin effects to those produced by skin irritants. Once sensitized, the body sets up an allergic reaction, and the skin may react severely if subsequently exposed to very small amounts of the wood dust. Cross-sensitization may develop where other woods or even non-wood materials produce a similar response." 3
Allergic Contact Dermatitis
An allergy is basically the negative health effects which result from the stimulation of specific immune responses. Allergic contact dermatitis is a form of delayed-type hypersensitivity reaction which is dependant upon cell-mediated immune function and the activity of T lymphocytes. The most frequent form of allergic reaction is to small molecular weight materials such as chemicals and proteins. These reactions are better known as contact hypersensitivity, skin sensitization, and allergic contact dermatitis.
This occurs in 2 stages:
Stage I (Induction Phase): Initial contact may result in the allergen penetrating the stratified squamous epithelial cells of the skin and binding to large dendritic (branched) white blood cells in the epidermis called Langerhans cells. The Langerhans cell (with the allergen on its membrane) migrates to a nearby lymph node where special white blood cells, called effector T-cells, are programmed to recognize the allergen. There are literally millions of effector T-cells roaming throughout the blood and lymphatic system, each with special receptor molecules on their membranes for a particular allergenic chemical. T-cells patrol our circulatory system looking for invading cells and viruses. 2
Stage II (Elicitation Phase): If you come in contact with the offending allergen during a subsequent encounter, an effector T-cell may encounter it bound to a Langerhans cell and attach to it by a complicated and specific recognition system. The effector T-cell then produces multiple clones and releases special proteins called lymphokines which attract a legion of different white blood cells, including macrophages and cytotoxic ("killer") T-cells. The new army of white blood cells releases cytokines or proteins which destroy everything in the vicinity including other skin cells, thus producing a blistering rash. 2
Milder effects range from redness (vasodilation) and itching (nerve injury) to small blisters (vesicles and bullae). Stronger effects can result in Anaphylaxis, which can occur in response to any allergen, while Anaphylaxis occurs infrequently; it is life-threatening and can occur at any time. Risks include prior history of any type of allergic reaction.
Here is a small list of popular woods that should be avoided.
We will continue to expand this list as we further our research.
Most of this information is taken from
Botanical Dermatology: Plants and Plant Products Injurious to the Skin. 4
Dalbergia spp (Rosewoods) With "the discovery of sensitizing quinones in other woods such as teak...led Schulz and Dietrichs (1962) to look for similar substances in Dalbergia nigra and Dalbergia retusa. They found three quinones which they called Dalbergia quinones A, B and C, and demonstrated by patch tests on patients that these were the sensitizers, the strongest being R-3,4-dimethoxydalbergione... They have now been found in most other Dalbergia spp." 4
Dalbergia retusa (Cocobolo) contains S-4'-hydroxy-4-methoxy dalbergione, R-4-methoxy dalbergione and other quinones and phenols. 4
Dalbergia cultrate (Burmese Rosewood) contains a dalbergione. 4
Dalbergia nigra (Brazilian Rosewood) contains R-4-methoxydalbergione and other quinones. 4
Dalbergia latifolia (East Indian Rosewood, Sonokoling) contain R-4-methoxydalbergione and other quinones. 4
Dalbergia cochinchinensis (Laos Rosewood, Thai Rosewood, Cochin Rosewood) contain R-4-methoxydalbergione and other quinones. 4
Dalbergia stevensonii (Honduran Rosewood, Nagaed Wood, Palissandre Honduras) contains a dalbergione. 4
Dalbergia decipularis (Tulipwood) contains a dalbergione. 4
Dalbergia frutescens (Tulipwood) contains a dalbergione. 4
Dalbergia. melanoxylon (African Blackwood) contains several quinones including S-4'-hydroxy-4-methoxydalbergione and S-4-methoxydalbergione. 4
Dalbergia cearensis (Kingwood, de Violette, Violet Wood, Violetta) contains a dalbergione, described as a very severe skin irritant, often leading to persistent ulceration.4
Dalbergia congestiflora (Mexican Kingwood) contains a dalbergione. 4
Dalbergia maritime (Madagascar Rosewood, Bois de Rose) contains a dalbergione. 4
Cordia dodecandra (Zericote, Ziricote) Cross reactions are possible with this species once sensitivity to R-3,4-dimethoxydalbergione (found in pao ferro and Dalbergia species), obtusaquinone (found in cocobolo), and macassar quinone (found in macassar ebony) have developed. 4
Cordia elaeagnoides (Bocote, Becote) Cross reactions are possible with this species once sensitivity to R-3,4-dimethoxydalbergione (found in pao ferro and Dalbergia species), obtusaquinone (found in cocobolo), and macassar quinone (found in macassar ebony) have developed. 4
Peltogyne densiflora (Purpleheart) "Dalbergiones have been isolated from the wood." 4
Tetraclinis articulata (Thuya Burl) The heartwood of this species is known to contain several dermatologically active compounds including thymoquinone, carvacrol, and ß- and ?-thujaplicins. 4
Tectona grandis (Teak) The "dermatic compounds" (sensitizers) lapachol (aka tecomin, a quinone), desoxylapachol, and lapachonole (aka lapachonone) where found in Tectona wood. Lapachol has been called "a known elicitor of contact dermatitis" and a "sensitizing agent." "Deoxylapachol and lapachenole...are potent contact allergens." "Local races of teak and even individual trees vary greatly in desoxylapachol content." "Lapachenole has been shown to be both irritant and sensitizing" by Sandermann & Barghoorn (1955). "Indonesian natives have long distinguished three grades of the wood, the poorest (Djati sempoerna) being liable to cause skin irritation"4
Pterocarpus soyauxii (Padauk) can cause irritation of the skin, dermatitis, and sensitizer. Can have naphthoquinones. Cross-sensitivity may occur with use of Bocote when sensitivity has been developed to related quinones. 5
Machaerium scleroxylon (Pau Ferro) has dalbergiones. It can cause dermatitis, itching, swelling, redness of face, scrotum, and hands. 4
Guibourtia tessmannii (Bubinga) "Dermatitis, possibly caused by sensitizing quinones." 6
Diospyros celebica (Macassar Ebony) contains macassar II, a ß-naphthol "derivative that may become oxidised in vivo to macassar quinone. This compound has been shown to have sensitizing properties in guinea pigs. Cross-sensitivity to other naphthoquinones" three found in zericote, pao ferro, cocobolo, becote, and padauk are possible. "Later testing confirmed sensitivity to R-3,4-dimethoxydalbergione (found in pao ferro), obtusaquinone (found in cocobolo), and macassar quinone (found in macassar ebony)." Wood of this specie is one of the only ones that these substances have been proven to be found in. "The yellow naphthoquinone pigment, plumbagin (methyl juglone) occurs in a colourless combined form and is liberated from root tissue by acid treatment. (Harborne 1966)... Plumbagin is also found in some species of the families Droseraceae, Ebenaceae, and Euphorbiaceae (Thomson 1971).... Plumbagin has an irritating odor and causes sneezing; it stains the skin to a purple color and has a vesicant action." 4
Cinnamomum camphora (Camphorwood) The wood contains camphor and borneol. Following cases of serious toxicity and even death in children, products containing more than trace quantities of camphor have now largely been withdrawn from the market (Reynolds 1996). "Can cause dermatitis and shortness of breath" and camphor causes mild heart stimulant activity. Topically applied, it can penetrate the skin. 4
Milletia laurentii (Wenge) can have central nervous system effects, give dermatitis, irritate skin, is listed as a sensitizer, and is oily. 5
Acer saccharum (Sugar Maple) "This species has been found to contain 2,6-dimethoxy-1,4-benzoquinone which is a known contact allergen" 5
Salix spp (Willow) contains salicin, a phenolic glucoside, and is a precursor of aspirin, also has saligenin, a known contact allergen. Willow is also listed as a sensitizer. 5
Betula spp (Birch) contain salicylates such as methyl salicylate, Cross-sensitivities could occur in those with aspirin allergies. Birch also listed as sensitizer. 5
Dymondwood is a manufactured wood product consisting of layers of birch veneer which have been dyed with aniline dye and then compressed under heat and pressure with acrylic resins into a dense, durable, highly polished material. Aniline dyes have been proven to be carcinogenic as well as sensitizing agents causing allergic contact dermatitis.
Aniline Dye (in Dymondwood)
Warning: this dye is also commonly used overseas to dye wood to make it appear as black ebony. Unfortunately, this practice is more common then you would believe. 7
Skin Contact: May be absorbed through skin. Symptoms of skin absorption parallel those from inhalation exposure. May cause skin irritation. Local contact may cause dermatitis. 7
Chronic Exposure: Aniline is a blood toxin, causing hemoglobin to convert to methemoglobin, resulting in cyanosis. Lengthy or repeated exposures may result in decreased appetite, anemia, weight loss, nervous system affects, and kidney, liver and bone marrow damage. Any exposure may cause an allergic skin reaction. 7
Skin Protection: Wear impervious protective clothing, including boots, gloves, lab coat, apron or coveralls, as appropriate, to prevent skin contact. 7
Environmental Toxicity: This material is expected to be very toxic to terrestrial life and to aquatic life.7

It is possible that once sensitized to one of these quinones that cross reactions to similar quinones and/or structures
can develop. Included at the bottom of this page is a list of some of the more popular woods that are not suitable to
wear due to these risks. There are other hardwoods that are notorious for causing dangerous reactions (which may
include surprisingly strong reactions such as cardiac and nervous system effects, cancer, and genotoxicity), such as:
afromosia (Periocopsis elata), Australian blackwood (Acacia melanoxylon), greenheart (Chlorocardium rodiei),



Page 3


mansonia (Mansonia altissima), sassafras (Sassafras albidum), and satinwood (Chloroxylon swietenia), as well as
various softwoods such as: cedar (Thuja spp.), hemlock (Tsuga spp.), pine (Pinus spp.), and yew (Taxus spp.);
however, these are not discussed here because we have fortunately not seen their attempted use in body jewelry.
Other compounds
Some of the other compounds that are known to cause harmful responses include: alkaloids and glycosides
(systemic effects, pharmacological rather than allergic), saponins (effective through broken skin only), phenols (the
strongest skin-sensitizers, especially the catechols of the poison-ivy family), stilbenes (which occur in allergenic
woods, but only chlorophorin and coniferyl benzoate are known to sensitize), terpenes (including delta-3-carene from
turpentine, sesquiterpene lactones and other sensitizing liverworts found on bark, and euphorbol and other complex
terpenes on uncertain toxicity found in the latex of Euphorbiaceae), coumarins and furocoumarins (photosensitizing
and may be partly responsible for skin reactions but has yet to be proven), and dalbergiones (severe skin irritants).
List of popular woods that should be avoided to minimize the risk of adverse effects
Most of this information is taken from: Botanical Dermatology: Plants and Plant Products Injurious to the Skin.
4
We will continue to expand this list as we further our research. Note that we are listing research specific to the
heartwood of trees; toxins can be found in a species that is not found in its wood. For example, cyanide is found in
apple seeds, but the fruit is edible, even though it is in close proximity to this toxin. "Toxic activity is specific to a
wood species. Knowing the exact species is important in establishing what the potential toxic effects may be.
Individual wood species... are very easily confused. For example, 'rosewood' may be used for up to 30 different
species; and an individual species may have up to ten different trade names (Hausen 1981). An additional difficulty
is that trees vary within a species. One specimen may contain low levels of its toxic agent and the next contain much
higher levels. So experience may not be a reliable guide."
5



Page 4


Dalbergia spp: (Rosewoods) "The discovery of sensitizing quinones in other woods such as teak...led Schulz and
Dietrichs (1962) to look for similar substances in Dalbergia nigra and Dalbergia retusa. They found three quinones
which they called Dalbergia quinones A, B and C, and demonstrated by patch tests on patients that these were the
sensitizers, the strongest being R-3,4-dimethoxydalbergione... They have now been found in most other Dalbergia
spp."
4
Dalbergia cearensis: (Kingwood, de Violette, Violet Wood, Violetta) contains a dalbergione, described as a very
severe skin irritant, often leading to persistent ulceration.
4
Dalbergia cochinchinensis: (Laos Rosewood, Thai Rosewood, Cochin Rosewood) contain R-4-
methoxydalbergione and other quinones.
4
Dalbergia congestiflora: (Mexican Kingwood) contains a dalbergione.
4
Dalbergia cultrate: (Burmese Rosewood) contains a dalbergione.
4
Dalbergia decipularis and Dalbergia frutescens: (Tulipwood) contains a dalbergione.
4
Dalbergia latifolia: (East Indian Rosewood, Sonokoling) contain R-4-methoxydalbergione and other quinones.
4
Dalbergia maritime: (Madagascar Rosewood, Bois de Rose) contains a dalbergione.
4
Dalbergia melanoxylon: (African Blackwood) contains several quinones including S-4'-hydroxy-4-
methoxydalbergione and S-4-methoxydalbergione.
4
Dalbergia nigra: (Brazilian Rosewood) contains R-4-methoxydalbergione and other quinones.
4
Also endangered.
Dalbergia retusa: (Cocobolo) contains S-4'-hydroxy-4-methoxydalbergione, R-4-methoxydalbergione,
obtusaquinone, and other quinones and phenols.
4
Dalbergia stevensonii: (Honduran Rosewood, Nagaed Wood, Palissandre Honduras) contains a dalbergione.
4
Acer saccharum: (Sugar Maple) "This species has been found to contain 2,6-dimethoxy-1,4-benzoquinone which is a
known contact allergen."
4, 7
Betula spp: (Birch) contains salicylates such as methyl salicylate. Cross-sensitivities could occur in those with
aspirin allergies. Birch is also listed as sensitizer.
5
Cinnamomum camphora: (Camphorwood) The wood contains camphor and borneol. Following cases of serious
toxicity and even death in children, products conta ining more than trace quantities of camphor have now largely been
withdrawn from the market (Reynolds 1996). "Can cause dermatitis and shortness of breath" and camphor causes
mild heart stimulant activity. Topically applied, it can penetrate the skin.
4
Cordia dodecandra: (Zericote, Ziricote) Cross reactions are possible with this species once sensitivity to R-3,4-
dimethoxydalbergione (found in pao ferro and Dalbergia species), obtusaquinone (found in cocobolo), and macassar
quinone (found in macassar ebony) have developed.
4
Cordia elaeagnoides: (Bocote, Becote) Cross reactions are possible with this species once sensitivity to R-3,4-
dimethoxydalbergione (found in pao ferro and Dalbergia species), obtusaquinone (found in cocobolo), and macassar
quinone (found in macassar ebony) have developed.
4
Diospyros celebica: (Macassar Ebony) contains macassar II, a ß-naphthol "derivative that may become oxidised in
vivo to macassar quinone. This compound has been shown to have sensitizing properties in guinea pigs. Cross-
sensitivity to other naphthoquinones" (three found in zericote, pao ferro, cocobolo, becote, and padauk) are possible.
"Later testing confirmed sensitivity to R-3,4-dimethoxydalbergione (found in pao ferro), obtusaquinone (found in
cocobolo), and macassar quinone (found in macassar ebony)." Wood of this specie is one of the only ones that these
substances have been proven to occur in. "The yellow naphthoquinone pigment, plumbagin (methyl juglone) occurs
in a colourless combined form and is liberated from root tissue by acid treatment. (Harborne 1966)... Plumbagin is



Page 5


also found in some species of the families Droseraceae, Ebenaceae, and Euphorbiaceae (Thomson 1971)....
Plumbagin has an irritating odor and causes sneezing; it stains the skin to a purple color and has a vesicant action."
4
Guibourtia tessmannii: (Bubinga) "Dermatitis, possibly caused by sensitizing quinones."
6
Machaerium scleroxylon: (Pau Ferro) has R-3,4-dimethoxydalbergione
7
, a strong sensitizer and irritant. It can
cause dermatitis, itching, swelling, redness of face, scrotum, and hands.
4
Milletia laurentii: (Wenge) can have central nervous system effects, give dermatitis, irritate skin, is listed as a
sensitizer, and is oily.
5
Wenge contains 2.6-dimethoxybenzoquinone.
7
Peltogyne densiflora: (Purpleheart) "Dalbergiones have been isolated from the wood."
4
Pterocarpus soyauxii: (Padauk) can cause irritation of the skin, dermatitis, and sensitization. It can have
naphthoquinones. Cross-sensitivity may occur with use of bocote when sensitivity has been developed to related
quinones.
5
Salix spp: (Willow) contains salicin, a phenolic glucoside, and is a precursor of aspirin; also has saligenin, a known
contact allergen. Willow is also listed as a sensitizer.
5
Tectona grandis: (Teak) The "dermatic compounds" (sensitizers) lapachol (aka tecomin, a quinone), desoxylapachol,
and lapachonole (aka lapachonone) where found in Tectona wood. Lapachol has been called "a known elicitor of
contact dermatitis" and a "sensitizing agent." "Deoxylapachol and lapachenole...are potent contact allergens." "Local
races of teak and even individual trees vary greatly in desoxylapachol content." "Lapachenole has been shown to be
both irritant and sensitizing" by Sandermann & Barghoorn (1955). "Indonesian natives have long distinguished three
grades of the wood, the poorest (Djati sempoerna) being liable to cause skin irritation."
4
Tetraclinis articulata: (Thuya Burl) The heartwood of this species is known to contain several dermatologically active
compounds including thymoquinone, carvacrol, and ß- and ã-thujaplicins.
4
Other wood related products
Dymondwood® is a manufactured plywood product consisting of laminated layers of hardwood (likely birch) veneer
which have been colored with mono-azo acid dyes and then compressed under intense heat and pressure with
phenol formaldehyde resin into a dense, durable, highly polished material. Interestingly, Bakelite, a type of early
thermoset synthetic resin, is a polymer of phenol with formaldehyde. Many Dymondwood® varieties go by cute trade
names, but it can usually be identified by it's appearance as a brightly colored wood product with consistently spaced
stripes in contrasting colors not normally appearing in untreated wood. Besides cropping up periodically in the body
piercing world as earplugs, it is common to find it utilized in other products such as pipes and bracelets.
Phenol, also known as carbolic acid or hydroxybenzene, is toxic and corrosive. The dangers posed by formaldehyde,
including it's role as a carcinogen, are also substantial. According to the MSDS for Dymondwood®, "Phenol and
formaldehyde may be released in small quantities from product under normal conditions." "Some people may
develop dermatitis from repeated and prolonged exposure to unfinished product." "Laboratory data indicates that
certain acid dyes may be mutagenic in animals."
8
The azo dyes (azo is a chemical compound containing one pair
nitrogen atoms with a double bond between them) may release aromatic amines if the azo linkages are broken down
via enzymes, or poss ibly via heat and photochemical reactions, though intact azo dyes are unlikely to be absorbed by
the skin. However, these aromatic amines have been linked to serious long-term health effects, including links to
cancer in humans, so the possibility of their presence is of grave concern. Incidently, azo dyes are sometimes used
as pigments in tattoo ink.
Unfortunately, dyes are also commonly used overseas to make lighter woods appear as black ebony. These
commonly include aniline or PPD. Aniline is a blood toxin that is easily absorbed through the skin, which may cause
allergic skin reactions and irritation, contact dermatitis, sensitization, is a possible carcinogen, and is considered very
toxic to terrestrial and aquatic life.

Hey

Thanks guys for all your help. All this information it's great stuff. 8) 8)

Yeah, if only we could get Jim to divulge a little more info we would be alright. ;D

I have heard that Bois D' Arc (Osage Orange) is toxix and should not be used to eat off of turned bowls etc. But you have to take it with a grain of salt without actual scientific eveidence because i just used those 3 too oft-used words "I have heard".
I don't remember where I read this. The fruit a.ka. "Horse Apples" that grow on them are toxic to humans but horses love them. This I know for a fact as my kids love to feed them to my Dads' horses.
Cockroaches and other pests hate them but a website that has sold them online for years can no longer make that claim because the FDA told them they cant make that claim. Silly FDA.

Emah, you never told us why you want to know this stuff. Spill the beans we are the curious types. And welcome to the FF.

Hey everyone

Sorry, for the late reply to your question kevjay I have just come back from my Easter holiday. It was a good break.

I want this information because I'm working on a toxic wood page for the Peterson website we often get people asking what information we have on this subject.

I didn't find a wide range of information on the World Wide Web so I thought I'd ask the people who work with wood everyday.

So thanks for all your input  8) ;) 8)

Emma

Glad you had a great break Emma.

Hope it helped or at least led you in the right direction. Please verify any of it before you pass it on like I said I don't know for 100% because I am repeating what I have heard passed down from generations but you are needing to know for sure before you give it to customers.
I'm sure you don't need me telling you that I am just reiterating that I have no data to back up anything I said. :)