Sweet pea-Lathyrus odoratus L.-Poisonous plant

Sweet pea

General poisoning notes:

Sweet pea (Lathyrus odoratus) is a summer annual commonly cultivated because of its beautiful fragrant flowers. The pods and seeds contain BAPN (beta-aminopropionitrile), which causes osteolathyrism, a syndrome characterized by skeletal deformities and aortic rupture. This chemical was first extracted from sweet pea plants and has since been found in some other members of the genus Lathyrus. Horses are more susceptible to this syndrome than other livestock. Most of the information on osteolathyrism is based on experimental work. This problem has not occurred in humans; instead, see neurolathyrins under grass pea (Lathyrussativus). In Canada, ingesting enough sweet pea to cause osteolathyrism is not likely (Selye 1957, Cheeke and Schull 1985).

Description:

Annual herbs, 50-200 cm tall. Stem climbing, much branched, somewhat hairy, winged. Leaves with branched ten­dril at apex; rachis winged; stipules semisagittate; leaflets 1-paired, ovate-oblong or elliptic, 20-60 × 7-30 mm, with pin­nate veins, rarely subparallel veins, margin entire. Raceme longer than leaf, 1-3(or 4)-flowered. Calyx campanulate, equally toothed and longer than tube. Corolla usually purple, or other colors, 20-30 mm. Ovary linear; style twisted. Legume brown-yellow, linear, 5-7 cm, pubescent. Seeds smooth.

Nomenclature:

Scientific Name: Lathyrus odoratus L.

Vernacular name(s): sweet pea

Scientific family name: Leguminosae

Vernacular family name: pea

Geographic Information

Widely cultivated in China and worldwide as an ornamental and cut flower. Plant or plant parts used in or around the home.

Toxic parts:

Seeds.

Toxic plant chemicals:

Beta-aminoproprionitrile.

Animals/Human Poisoning:

Note: When an animal is listed without additional information, the literature (as of 1993) contained no detailed explanation.

Horses

General symptoms of poisoning:

Aneurysm, gait, rigid, scoliosis.

Notes on poisoning:

Literature reports of osteolathyrism show that horses are particularily susceptible. Symptoms include skeletal deformity, such as long bone curvature, kyphosis, scoliosis, osteoporosis, and poor development of connective tissue. Aortic rupture also occurs. These effects are due to defective synthesis of collagen and elastin tissue caused by BAPN (Cheeke and Schull 1985).

Rodents

General symptoms of poisoning:

Abortion, aneurysm, bones, fragile.

Notes on poisoning:

Experimental feeding of sweet pea seeds to rats has caused symptoms of osteolathyrism, including the production of fragile bones, muscle atrophy, fatty bone marrow, hernias, thin skin, and scoliosis (Selye 1957, Cheeke and Schull 1985).

Turkeys

General symptoms of poisoning:

Aneurysm.

Notes on poisoning:

Experimental feeding of the toxic chemical beta-aminopropionitrile (BAPN) caused aortic dissecting aneurysms in turkey poults. Mortality was quite high as a result. See additional information under general notes ofLathyrus sativus (Lalich et al. 1957, Simpson and Cardeilhac 1983).