From: Nat of WorldStove [[email protected]]
Sent: 2011-01-26 04:29:34 MET
To: [email protected]
Subject: [Stoves] Dangers of Jatropha and some good news
Dear Stovers,
While I can appreciate the enthusiasm with which many arenow, at least
conceptually, tackling the use of Jatropha as a fuel for stoves,I feel
compelled to remind the group that, we as a community have as ourprimary
objective the safety and health of those who need clean cookstoves. To this
end, statements thattoxicity of Jatropha is eliminated by heat are dangerously
misleading andignore decades of evidence.
The source referred to (http://www.tnau.ac.in/tech/swc/evjatropha.pdf) states
that?.
?Like Castor oil, the Jatropha oil and cake contain tracesof
toxins. The components associated with toxicity can be
denatured or inactivated by heat. The toxic components in
Jatropha cake are curcin a phytotoxin similar to ricin in castor
and HCN in young Sorghum leaves andTapioca rind.?
What is ricin? In1978, the Bulgariandissident Georgi Markov was assassinated
with a bit of ricin poked into him onthe tip of an umbrella. One milligramof
this toxin in the bloodstream constitutes a lethal dose. Ricin is currently
classified asa potential chemical weapon. Additionally,heat labile toxins are
not the only toxins present many varieties of Jatrophaalso may contain
hydrocyanic acid (CRC Critical Reviews in Toxicology 1977)
TOXICITY OF JATROPHA
Toxicity of Jatropha has been studied for far longer thanmost stove programs
have existed. With publications in peer reviewed journalsdating at least back
to 1976 (Alpin), and newer articles from the NationalAcademy of Science where
it is noted that ?the resultant seed cake and othervegetative tissues are
highly toxic.?
(http://www.tnau.ac.in/tech/swc/evjatropha.pdf;http://www.pnas.org/content/106/35/E92.full)
(Jongschaap,R. et al. 2009. The water footprint of bioenergy from Jatropha
curcas L PNAS : 106 no. 35 E92). Themost recent compendium being published
only last year. Even documents in favor of the use ofJatropha oils in stoves
make careful note of its toxicity. For example:
http://www.snvworld.org/en/Documents/FACT_Foundation_Jatropha_Handbook_2010.pdf
See also?
http://www.inchem.org/documents/pims/plant/jcurc.htm#SectionTitle:3.3The
toxin(s)
Although the introductory pdf quoted above
(http://www.tnau.ac.in/tech/swc/evjatropha.pdf ) claimsthat some toxins in
Jatropha can be destroyed ?by heat? This does NOT mean thematerial is safe to
burn. The oils inJatropha are highly volatile and would certainly be carried
in smoke emitted atthe beginning or the end of ignition. Here we can be guided
by warnings concerning another plant producingvolatile and toxic oils, poison
ivy, the literature is replete with warningsagainst burning this plant. For
example, http://www.hort.purdue.edu/ext/HO-218.pdf That states, ?NEVER burn
poison ivy! The smoke from burning the plant containsparticles that can cause
serious injury to the eyes, skin, and respiratorytract.? And toxicological
studies would indicate that this cautionary statementshould be applied to any
toxic biomass where the toxins can vaporize.
Clearly even the handling of Jatropha come withgreat risks, risks which can be
reduced with the use of protective suits andequipment, but to this day, in my
many travels, I have not seen anyfieldworkers in Jatropha fields provided with
even gloves
Risks
The risks associated with the handling of Jatropha include but are not limited
to:
1. Dehydration and cardiovascular collapse
2. Haemorrhagic gastro-enteritis.
3. Central nervous system depression.
4. Kidney failure
5. Liver failure
6. Blindness
7. Cancer
Christa correctly notes that Jatropha is being usedas a soil amendment but
please remember that because of the thermo-chemicaltransformation that occurs
during pyrolysis, without testing of biochar, it isnot safe to assume that what
is safe to place in soils as plant matter, willalso lead to the production of
safe biochar. Our tests, in fact, have indicatedthat oil rich fuels such as
karité and Jatropha can result in the production ofbiochar with higher levels
of polyaromatic hydrocarbons. So, as Otto noted ofemissions, I would like to
also note of biochar, that unless it is tested fortoxicity we can not, and
should not, assume it is safe. Otto?s point is particularly well taken
thatmost emissions protocols so far test for fine particles, and CO and CO2
butalmost no test tests for toxicity of biomasses intended for use in stoves.
CANWE AS A COMMUNITY SUPPORT THE EVICTION OF NATIVE PEOPLE, THE ELIMINATION
OFBIODIVERSITY, AND GREATER DEMANDS ON WATER?
WhileI only touched on this in my last email, let us take a step back and ask
wherethe supposed surplus of Jatropha seed cake would be coming from.. To
provide atheoretical use for its byproduct is seen as a justification, by some,
for theelimination of local biodiversity in the name of big oil. Even if
Jatropha were not toxic, can we as acommunity allow our stoves to be used as an
excuse for deforestation? But do not take my word for it, ask thosewho are
having Jatropha plantations forced on them who eloquently make thepoint in this
video:
http://www.youtube.com/watch?v=XiqMS6iglNQ
OTHER ENVIRONMENTAL CONCERNS.
As a final note, I now see many requests for shipments ofseedcakes to be sent
to the United States for testing. The import of plantmatter cannot generally be
done without USDA import permits. This restriction was created to avoid
newplant species epidemics such as those which caused the loss of the
AmericanChestnut when one small tree was brought to a New York botanical show
in 1904,and the loss to the American Elm because of a shipment of logs from
France inthe 1930s. Permit applications can be found here:
http://www.aphis.usda.gov/plant_health/permits/plantproducts.shtml
The process is not immediate nor is it guaranteed. For this reason we conduct
our tests duringlocal pilot programs and work closely with local universities.
A practice I ampleased to have seen now emulated by other stove programs.
IN CONCLUSION
I am neither stating that we should or should not explorethe use of Jatropha or
any other available waste biomass. However, to begin a study without
firsttesting for the risks from the resulting emissions and safety of the
resultantbiochar would seem to go against all that this community and this list
standsfor. As a positive final thought, noneed to reinvent the wheel.. There
are any number of organizations who havededicated decades to determining
toxicity of plants. If you are designing a newstove for a specific biomass or
tuning an existing one to be optimized for usewith a specific biomass, why not,
first of all, check out any number oforganizations like IPCS (International
Program on Chemical Safety)
http://www.inchem.org/documents/pims/plant/jcurc.htm#SectionTitle:3.3The
toxin(s)
This way we will never loose sight of the needs of thepeople we are trying to
help, no matter how temping a newly available feedstockmay be.
Cordially yours
Nathaniel Mulcahy
www.WorldStove.com
Today's Topics:
1. Heat destroys Jatropha toxins Re: jatropha, stoves, and
biochar. (Paul S. Anderson)
Stovers,
The cautionary notes given by Nat M. and Otto F. should be taken
seriously. However, they also need to provide scientific evidence to
support their statements.
Evidence implying the OPPOSITE of what was stated is the following:
from http://www.tnau.ac.in/tech/swc/evjatropha.pdf
Like Castor oil, the Jatropha oil and cake contain traces of
toxins. The components associated with toxicity can be
denatured or inactivated by heat. The toxic components in
Jatropha cake are curcin a phytotoxin similar to ricin in castor
and HCN in young Sorghum leaves and Tapioca rind and
purgative oil as in castor and croton oil. Heat treatment or the
combination of heat and chemical (NaOH and NaOCl)
treatments can inactivate the above toxic components.
**** Apparently heat destroys the toxins. Good news that has been out
of sight. Publication date is not evident.
--
Paul S. Anderson, PhD
Known to some as: Dr. TLUD Doc Professor
Phone (USA): 309-452-7072 SKYPE: paultlud Email: [email protected]
Quoting Nat of WorldStove<[email protected]>:
Dear All
Today's jatropha thread has been a grand discussion. I would like to
express some concerns however regarding jatropha.
There are many jatropha genotypes. The primary reason people are
planting Jatropha is because it can be used to
produce a high quality fuel oil. While I will not address my
concerns regarding the introduction of non native species into certain
ecosytems , other concernes are more pertinent to this list and
should be mentioned. It should be noted that many jatropha
genotypes are highly toxic. Short term,exposure to these toxins can
cause death and blindness, and the long term
carcinogenic effects of phorbol esters found in many genotypes of
jatropha have been documented for years. While there
are some less toxic varieties of jatorpha (native to Mexico) they do
not have the same crop yields as their more toxic relatives
and so it is safe to assume that much of the available waste will be
of the more toxic variety.
In the cases where jatropha is being considered not only as a fuel
for cooking, but also to produce biochar it should be noted
that the resultant content of PAH?s in some of the biochar produced
with jatropha is well beyond what is considered safe for
humans and should not be used in soils intended for food production.
I am all in favor of using agricultural residues and waste but would
like to echo Otto?s wise advice to test before we promote
the use of new fuels. After all plastics also work very well in
gasifieing stoves but I would certainly not advise using them. While
there has been talk of setting up stove test centers I would also
recommend centers to test for the safety of fuels intended
for cooking and fuels intended for biochar production.
Cautiously yours,
Nat of WorldStove
