By Ashley Follette (SCNM ND student), based on the powerpoint slides of Dr. Walter Crinnion ND
Solvent
Benzene
Uses
-made from petroleum
-top 20 cmpds
-used to make styrene,
cumene (resins),
cyclohexane (synthetic
fibers)
-used in mfcr of drugs,
pesticides, dyes, cmpds
Exposure/Sources
-Airborne: combustion of gasoline;
cig smoke (32 cigs/d = 1.8mg
benz/d), pumping gas, indoor air
freshners
-Other: glue, paint, furn. wax,
detergent; house w/ attached
garage; outside air near chem. &
paint plants
-well water contam. (from leaking
gas station storage tanks)
½ life
-biphasic: initial clearance from
body is 1 hr, what’s left takes 24
hrs
-neurotoxic, but not biocumulative
Ethylbenzene
-found naturally in crude
oil
-used to make styrene
-used as solvent &
additive in gas & aviation
fuel
-gas & gas exhaust
-carpet & tile glues
-paints & varnishes (high in marine
paints)
-cigarette smoke
-contaminated groundwater
-dermal absorption for spray
painters
-gas
-auto exhaust
-cigarette smoke
-paint & varnish fumes
-dermal exposure from contact w/
gas & furniture finishes
-12 hours
-majority should be cleared
through urine w/in 2 days of
exposure
-half-life can be expended if more
solvents are involved
Xylene
(dimethylbenzene)
-top 30 chems produced
in U.S.
-“safe” replacement for
benzene in gas (doesn’t
cause aplastic anemia)
-printing, rubber, &
leather industries
-cleaning agent, in paints,
paint thinners, &
varnishes
-3 isomers of xylene (dimethylbenzene): meta-xylene, othro-xylene, para-xylene
-mixed xylene is a mixture of the 3 isomers & usually contains 6-15% ethylbenzene
Toluene
-high production chem.
-fumes of paints, glues, solvents,
(methylbenzene)
from crude oil
gas
-as a solvent
-working in places where these
-to make other chemicals cmpds are used regularly
(benzene, trinitrotoluene, (painters, nail salons, etc)
toluene diisocyanate)
-nail polish, stain removers,
-minor component of gas carburetor cleaners, cigarette
& octane-boosting
smoke, auto exhaust
additives
-higher levels found in smokers,
-majority absorbed (mostly
inhaled) leaves body w/in 18 hrs
-small amt. (4-10%) stored in fat
– takes longer to exit body
-takes longer to clear from a
person w/ more adipose tiss
Adverse effects
-bone marrow probs: anemia,
thrombocytopenia, leucopenia, cancers (acute
myeloid leukemia(AML) & aplastic anemia)
-↑risk of leukemia, breast can, multiple
myeloma, Hodg.lymph, & NHL
-male infertility
-reduced infection fighting (from airborne exp)
-abnorm. long periods, female infertility,
↑miscar rate
-UPS drivers, airport workers, flight attendants,
freq flyers
-presence of ethylbenzene & xylene prolong the
time toluene is present in the blood
-neurotoxic “brain fog” (chronic or acute CTE)
-bone marrow probs (same as benzene)
-hearing loss
-↑ chemical reactivity (MCS)
-neurotoxic “brain fog” (acute or chronic CTE)
-fatigue
-headache, depression, mood changes
-adversely affects learning, behavior, & memory
in offspring exposed in utero
-from 2 studies done, the 3 most common
symptoms from neurotoxicity of xlyene: fatigue,
dry throat, increased thirst
-aspirin, benzene, & alcohol block
the clearance of toluene &
increases its blood levels
-6 hrs
-most common symptoms: fatigue, impaired
memory, impaired concentration, irritability,
headaches, labile mood, depression
-neurotic behavior, dizziness, insomnia
-“checkers” – have to go back & check things
that they have already done (ex: turning off
stove)
-psychomotor coordination problems
-study: neurotoxicity amongst printers – 3 most
By Ashley Follette (SCNM ND student), based on the powerpoint slides of Dr. Walter Crinnion ND
-paint, paint thinners,
ppl who drink regularly, ppl
common symptoms: fatigue, impaired mem,
fingernail polish,
exposed to pain & lacquer
impaired concen
lacquers, adhesives,
thinners
-shipyard painters: high scores for neurotic
rubber in some printing,
behavior, signif. probs w/ STM, concen, fatigue,
leather tanning, latex
dizzy, insomnia; press. in chest & perspiration
paint, Glade air freshener
w/o work; “checkers”
-Ppl w/ 15 min exposure to 15 ppm showed cognitive impairments, esp. short & long-term mem, psychomotor coord.
-Retired painters still have CTE (low motor ability, reasoning, & mem)
-female workers – more probs w/ manual dexterity, visual scanning, verbal memory – the toxicologist & enviro ppl said these women did not fit into toluene toxicity category
Styrene
-high production chem.
-gas
-8-9 hrs in blood
-impaired rxn time & vestibular fcn
(>13 bill lbs produced in
-auto exhaust
-2-4 days in adipose
-reduces MAO-B activity in platelets
2006 US)
-cig. smoke
-presence of toluene &
-cognitive disorders: short-term verbal mem
-in polysterene plastics & -paint & varnish fumes
trichloroethylene reduce
impairement, ↓ verbal learning, impaired logical
resins that make: plastic
-emissions from photocopiers &
metabolism of styrene
mem
packaging, disposable
laser printers (getting more
-most frequent symptoms: ha, dizzy, lightcups/containers,
exposure from home offices)
headed, fatigue, irritability, mem loss, feeling
insulation, adhesives,
-dermal exposures from gas, paint,
“drunk”
fiberglass, synthetic
furniture finishes
-impaired color vision
rubber & latex
-ingestion exposure: food that has
-study: workers w/ 8.6 yrs exp – highest
-benzene & ethylbenzene been stored or heated in
symptom: impaired logical mem, visualmotor, &
used to make styrene
Styrofoam
visualconstructive ability
-study: dizziness very consistently found in those
exposed (very uncommon in those not exposed);
to test pt, have stand on tip-toes w/ eyes closed
Trichloroethylene
-dry cleaning
-very hard to clear bec it is a
-cranial nerve effects, esp. trigeminal
-ground water in Tuscon
chlorinated solvent – gets stored
-persons w/ TCE contaminated well water: ↑
in fat, brain fat!
hearing impairment (signif.), ↑ speech
impairments, ↑ resp. probs
-multiple neurobehavioral changes (response
time, sway, mem, visuospatial & movt tests)
Hexane
-commonly used solvent
-gas, auto exhaust
-acute exp – CNS disturbances: ha, mental
(consists of n-Hexane &
-quick-drying glues
irritability, paresthesias
its isomers of 2-jet fuel & exhaust
-chronic exp – peripheral neuropathy – muscle
methylpentane & 3-presence of methylpentanes w/o
weakness, loss of sensation, impaired gait
methylpentane)
n-hexane typically indicate that
-can cause demyelination & nerve fiber degen.
-in glues, adhesives,
exposure is neither recent nor
-balance probs & CTE
paints, gas, jet fuel
ongoing (historic exposure bec n-distal axonal swelling leading to neuropathies &
hexane became methylpentane)
muscular atrophy
-abnormal color vision
-abnormal sway testing (vestibulocerebellar &
spinocerebellar changes)
By Ashley Follette (SCNM ND student), based on the powerpoint slides of Dr. Walter Crinnion ND
-farmers w/ regular exposure had levels lower than drivers regularly exposed to exhaust fumes (both were 95th percentile) – drivers exposed to a lot!!!
-study: 95th percentile level for the presence of n-hexane in blood as range of 403-812 ppb – ridiculously high levels! Ubiquitous & hard for body to clear!
Formaldehyde
-histology technicians: reduced dexterity, balance, coord, choice performance on neurobehavioral testing; 10X increase in lightheadedness &
dizziness; 5X increase in loss of balance; pronounced symptoms in older ppl
-long-term exposure: excessive fatigue, somnolence, ha, mem trouble, irritability, mood instability, cognitive difficulties