Cold injury

Mark Wilcox, Preventing Cold Injury. Yuma County, Cooperative Extension, University of Arizona,... 

Cold injury (frostbite and hypothermia) and impaired ability to work are dangers at low temperatures and when the wind-chill factor is low. To guard against them, the personnel at an industrial site should (a) wear appropriate clothing, (b) have warm shelter readily available, and (c) carefully schedule work and rest periods, and monitor workers physical conditions. 

Hicks, L. M., Hunt J. L. and Baxter C. R. (1979). Liquid propane cold injury a clinicopathologic and experimental study. /. Trauma 19, 701-703. 

Morita-Fujimura Y., Fujimura M., Kawase M., Chen S. F., and Chan P. H. (1999) Release of mitochondrial cytochrome c and DNA fragmentation after cold injury-induced brain trauma in mice possible role in neuronal apoptosis. Neurosci. Lett. 267, 201-205. 

Cold weather decreases the total number of injuries, but it does produce a variety of injuries and illnesses that are unique to colder temperatures. Cold injuries can be divided into local cold injuries and the systemic state of hypothermia. Hypothermia is further classified as mild, moderate, and severe. Local cold injuries include frostbite, frostnip, and chilblains. Barnes (2002) describes the spectrum of cold injuries ... 

Frostnip. Frostnip is the precursor to frostbite. It is a superficial cold injury without ice crystal formation or tissue damage. Clinically, the involved injury is pale from vasoconstriction, and mild burning or stinging is usually felt. Symptoms improve with rewarming, and no long-term tissue damage occurs. 

Skin abnormalities Normal Pale Erythema Cyanosis Pigmented Cold Injury ... 

Spears turn brown, may get soft or wither and dry. Cause Cold injury. Cut and discard damaged spears. Cover spears with mulch or newspaper when freezing nights are predicted. 

Basil is rarely troubled by pests or diseases. Protect plants with row covers when temperatures drop below 40°F or dark spots caused by cold injury may appear on leaves. Fungi may also cause dark spots on foliage. Remove spotted leaves and spray foliage with compost tea or sulfur if problem is severe. If leaves are mottled yellow with tumed-down edges, plants may have cucumber mosaic virus. Destroy infected plants. See the Herbs entry beginning on page 116 for other problems. 

Pods pitted and browned. Cause Cold injury. Most cultivars may be damaged at temperatures below 45°E Protect late crops with row cover. 

Heads with black or discolored centers. Causes Fungal rot cold injury. Broccoli heads rot when water collects between the individual flower buds. Avoid wetting heads when watering. Cold weather can also cause black areas in the center of heads. Protect plants with row cover when temperatures below 40° F are predicted. 

In addition to problems outlined in the cabbage entry, a combination of cold injury and viral disease can cause leaves with black specks. Destroy infected plants. Caterpillars will bore small holes into sprouts see Leaves with large, ragged holes on page 56 for more details and controls. Plants deficient in potassium have poorly developed sprouts Spray with seaweed extract at transplanting and repeat several times to prevent problems. Check potassium levels with a soil test, and amend as necessary. 

Seed pods pitted, discolored, or with water-soaked areas. Cause Cold injury. Prevent damage by protecting plants with row cover when cold nights are expected. 

Cause Heat or cold injury. If temperatures are above 85°E protect plants with a thick straw mulch and keep soil moist. Protect overwintering onions with mulch, or dig and store just above freezing. 

Fruit with faded or gray-white, sunken patches or pits. Causes Sunscald cold injury. Green or ripe fruit can be sunscalded. Damage shows up as a large, sunken patch on the exposed side. Patches turn dry and may develop black mold. Control leaf diseases to prevent defoliation, so fruit will be shaded and protected from direct sun. Stake plants. 

Roots soft and shriveled. Cause Cold injury. Protect roots with mulch below 32°E... 

Potatoes turn spongy in storage. Cause Cold injury. Cool temperatures can damage sweet potatoes. Harvest when air is above 50°F and store above 50°F to prevent injury. 

Fruit gnarled and malformed with dry scars near the blossom end. Cause Cold injury. Cat-facing, as this symptom is also called, is caused by prolonged cool weather during blossoming. Poor pollination may be partially responsible. Protect plants with row cover until nights remain above 55°E... 

Roots with small, water-soaked spots or pits on sur ce. Cause Cold injury. Protect plants with mulch if temperatures are below 30° E... 

Most important, observe plants frequently. Rarly detection is the key to easy ajid effective disease control. If you catch a disease early on, a simple control such as handpicking the infected part may eliminate the problem. A few days of undisturbed development, however, may be all that disease needs to threaten the life of your plants. And as it is weakened by the disease, the infected plant becomes more susceptible to other problems. Plants with root rot, for instance, are more likely to suffer from winter cold injury and drought damage than healthy plants. And plants damaged by air pollution become more susceptible to insect attack. By keeping a watchful eye on your plants, you can spot diseases before they get out of hand. 

Symptoms Symptoms of cold injury can be similar to sunscald symptoms blotchy, water-soaked areas on leaves. Shoot tips often die back (see stem damage photograph on page 396). 

Winter injury. See Cold injury Wirestem, cabbage and, 54 Wire worms, 336,336 bait traps for, 435 bean and, 33 carrot and, 61 corn and, 77 Gladiolus and, 106 lettuce and, 138 nematodes and, 457 onion and, 156 potato and, 188,189, 191 sod crops and, 418 sweet potato and, 221,222 Wisteria. 251-52... 

Ice put an ice bag or cold pack to the injured area for 20 minutes 4-8 times a day. A plastic bag filled with crushed ice and wrapped in a towel can be used. Remove the ice after 20 minutes to avoid cold injury. 

Sotiropoulos G, Kilaghbian T, Dougherty W, et al. 1998. Cold injury from pressurized liquid ammonia a report of two cases. J Emerg Med 16(3) 409-412. 

Murakami, K., Kondo, T., Yang, G., Chen, S.F., Morita-Fujimura, Y., and Chan, P.H., Cold injury in mice A model to study mechanisms of brain edema and neuronal apoptosis, Prog. NeurobioL, 57(3), 289, 1999. 

Erythema Red area of the skin caused by heat or cold injury, trauma, or inflammation. 

The combination of ambient temperature and wind speed is called windchill. Wind-chill may be used to predict the risk of freezing of the exposed skin and to predict the amount of manual dexterity decrease (Daanen, 2009). The windchill index, as an estimator of cold injury risk, is part of an ISO standard (11079, 2007). In the heat, wind has a cooling effect by enhancing convective and evaporative heat loss. 

The temperature of the shell is often assessed using skin temperature according to ISO standard 9886 (ISO 9886, 2004). The lowest temperature of the skin is about —1 °C. Lower values lead to freezing cold injuries. The highest value a skin can tolerate is dependent on time of exposure. Long exposure of values higher than 44 °C may lead to bum wounds. 

Compressed gas cylinders containing anhydrous ammonia may present a cryogenic (cold injury) hazard. The liquid anhydrous ammonia is very volatile and, like liquid nitrogen, will immediately freeze the skin. 

Valves may be left open or broken off, and large amounts of the product may be released. Individuals involved in the theft can be injured or killed. Persons with cryogenic injuries (cold injuries to the skin—these look like regular thermal bums) or lung injuries involving ammonia may be involved in the manufacture of methamphetamine. 

The rate of heat transferred to the environment from the body can lead to certain heat and cold injuries and illnesses. 

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