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in 1996. EXTOXNET no longer updates this information, but it may be useful
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EXTOXNET primary files maintained and archived at Oregon State
Revised June 1996
Trade and Other Names:
Trade names of this product are Natur Gro R-50, Natur Gro Triple
Plus, Ryanicide, and Ryan 50.
Ryania is a General Use Pesticide (GUP). It is classified as EPA
toxicity class III - slightly toxic. Products containing this
pesticide are labeled with the Signal Word CAUTION.
Ryania is a botanical insecticide made from the ground stems of
Ryania speciosa, a native plant of tropical America. The
principal alkaloid in this stem extract is ryanodine, which makes
up approximately 0.2% of the product. Ryania is highly toxic to
the fruit moth, coddling moth, corn earworm, European corn borer,
and citrus thrips, but it is ineffective against the cabbage
maggot, cauliflower worm, and boll weevil. Ryania is a complex
mixture of many compounds; thus, no single structure would
Formulation: Ryania is
a botanical insecticide made from the ground stems of Ryania
speciosa, a native plant of tropical America. The principal
alkaloid in this stem extract is ryanodine which makes up
approximately 0.2% of the product. Ryania is a complex mixture of
many compounds, thus no single structure would represent it.
- Acute toxicity: Symptoms of poisoning
include vomiting, weakness, and diarrhea . Rigidity
of the muscles and depression of the central nervous
system can lead to a coma and death from respiratory
failure at high doses . The reported oral LD50s for
ryania in rats are 1200 mg/kg and 750 mg/kg .
Reported LD50s in guinea pigs and rabbits are 2500 mg/kg
and 650 mg/kg respectively . Dogs appear to be much
more susceptible with an LD50 of 150 mg/kg . The
observed toxicity is apparently due to the ryanodine
alkaloid, which is 500 to 700 times more toxic than the
crude powder . A 2 to 5 mg/kg dose of ryanodine
elicited symptoms in the frog and mouse . The dermal
LD50 in rats is above 2000 mg/kg. Inhalation data
reported semiquantitatively indicate that ryania may be
of low toxicity via inhalation .
- Chronic toxicity: Rats and guinea pigs
were fed diets containing 1% ryania powder (approximately
600 mg/kg/day for rats and 361 mg/kg/day for guinea pigs)
during a 5-month period  and showed no symptoms. Rats
fed 5% diets (approximately 2700 mg/kg/day) experienced
severe weight loss and 100% mortality within 25 days
- Reproductive effects: No data are
- Teratogenic effects: No data are
- Mutagenic effects: No data are currently
- Carcinogenic effects: No data are
- Organ toxicity: Very large doses of
ryania powder (from 1200 to 2700 mg/kg/day) in the diets
of rats produced hemorrhages in the pancreas and
intestines. They also produced lung complications in the
test animals . Ryania mainly exerts its effects on
striated (skeletal) muscle tissue and cardiac smooth
muscle, although evidence for effects on other smooth
muscles (e.g., bladder) is mounting [59,60].
- Fate in humans and animals: No data are
- Effects on birds: Ryania is moderately
toxic to birds and wildfowl. Some LD50 values include:
wild birds, 1.78 mg/kg; pigeons, 2.31 mg/kg; and quail,
13.3 mg/kg . Chickens fed for 6 months on diets of 1%
ryania showed no symptoms and did not have any evidence
of cumulative effects .
- Effects on aquatic organisms: It is
considered moderately toxic to fish. Reported 96-hour
LC50s are 3.2 mg/L in rainbow trout and 18.5 mg/L in
- Effects on other organisms: No data are
- Breakdown in soil and groundwater: No
data are currently available.
- Breakdown in water: The toxicologically
active portion of ryania, ryanodine, is water soluble but
stable during storage and stable upon exposure to light.
- Breakdown in vegetation: Ryanodine is
not considered to be poisonous to plants . The major
degradation product or ryanodine is anhydroxyanodine
- Appearance: Ryanodine is a very stable
solid at room temperature .
- Chemical Name: Ryania
- CAS Number: 15662-33-6
- Molecular Weight: 493.54
- Water Solubility: 100-10,000 mg/L ,
s. in water
- Solubility in Other Solvents: s. in
methanol, acetone, ether, and chloroform; i.s. in benzene
and petroleum ether 
- Melting Point: decomposes @ 219-220 C
- Vapor Pressure: Not Available
- Partition Coefficient: Not Available
- Adsorption Coefficient: Not Available
- ADI: Not Available
- MCL: Not Available
- RfD: Not Available
- PEL: Not Available
- HA: Not Available
- TLV: Not Available
125 W. Seventh St.
Wind Gap, PA 18091
- Phone: 610-863-6700
- Emergency: 610-863-8050
References for the information in this PIP can be found in
Reference List Number 2
information in this profile does not in any way replace or
supersede the information on the pesticide product labeling or
other regulatory requirements. Please refer to the pesticide