Occupational Ocular Problems in Sports, Driving, Agriculture & Industries

Sabina PoudelB. OptometryInstitute of Medicine

PRESENTATION LAYOUT

Introduction Environmental and occupational optometry Classification of occupational ocular

hazards and their effects Occupational ocular problems in sports Occupational ocular problems in driving Occupational ocular problems in agriculture Occupational ocular problems in industries

IntroductionOccupational eye disorders represent a complex group of

Traumatic injuries

Harmful exposures

Uncorrected and undiagnosed ocular diseases

Eyestrain and fatigue

Miscellaneous ocular complaints

Goldsmith et.al. 2007

• Almost all adults spend a significant portion of their lives working in a variety of occupational settings

• Exposure to hazards in the workplace can cause or exacerbate ocular illness

• It is crucial to know The environments of the patients

The type of work they do

How it may affect their eyes, vision and health

Environmental and Occupational Optometry: Introduction

Environmental Optometry- An Essential Part of Primary CareBranch of optometry that broadly considers the relationship of people’s eyes and vision to all aspects of their environments, including home, school, work, recreation, transportation, underwater and outerspace

Occupational OptometryBranch of environmental optometry that considers all aspects of the relationship between work and vision, visual performance, eye safety and health

Worker’s eyes and

visual system

Worker and

workplace environme

nts

• Prevention of work related eye diseases, injuries & vision disorders

• Enhanced performance of workers on the job

Major Priorities

Occupational ocular hazards can be broadly classified asType of hazards Causative agents

Mechanical Flying objectsContact with fixed objectsDusts , powdersHot solids

Chemical Dusts , powdersLiquids , droplets , splashesVapours , fumes , gases

Radiation Glare from visible lightShort circuit electric arcUltraviolet raysInfrared Laser sources

Combinations of the above

Mechanical HazardsComprises about 70 – 80 % of all work related eye injuriesLarge range of severity- wide range of missile size, mass and speed that is involved

Large slow moving missiles: Contusive or concussive injuries to eye

and adnexa Contusion results from direct blow to the

eye Concussion arises from conduction of

energy from a remote site to target tissue

Missile with rough surface or sharp edges: Lacerations and abrasions

Foreign bodies in the eye: May be superficial, imbedded or

intraocular, depending on size, shape and speed of the body

Ferrous foreign body should be removed as quickly as possible to remove siderosis (formation of rust in ocular tissues as a result of oxidation of iron contained in foreign body)

Particles less than 0.5 mm diameterToo small to cause penetrating ocular injuriesMay become embedded in the ocular surface if at high speedCause foreign body sensation upon contact with the eye

Chemical Hazards common causes of chemical injury:

Alkali Common sourcesAmmonia Fertilizers ,

refrigerantsLye Drain cleaners

Lime Plaster , mortar, cement

Magnesium hydroxide

Sparklers

Potassium hydroxide Caustic potash

Acid Common sources

Sulphuric acid Industrial cleaners,battery acid

Hydrofluoric acid Glass polishing,glass frosting,gasoline alkylation

Acetic acid vinegar

Sulphurous acid Fruit and vegetable preservative, bleach

• Alkaline solutions penetrate the eye rapidly by saponification of cell membranes and cause more severe injuries than acids of same concentration

• Acids cause coagulation of proteins of ocular tissue which acts as a barrier for further penetration

Electrical Hazards Electrocution may result in damage to the

central nervous system In rare cases , an electric cataract can be

observed

Optical Radiation HazardsOptical radiation ranges from 200 nm to 1 mm in the electromagnetic spectrum

UV C (FAR) 200 t0 290 nm

UV B (MIDDLE) 290 to 320 nm

UV A (NEAR) 320 to 380 nm

VISIBLE LIGHT 380 to 760 nmIR A (NEAR) 760 to 1400 nm

IR B (MIDDLE) 1400 to 3000 nmIR C (FAR) 3000 nm to 1 mm

Transmission of Radiation by the Ocular Media

UV (nm) VISBLE (nm)

IR (nm)

Tear layer 290 - 380 380 - 760 760 - 3000

Cornea 290 – 380* 380 - 760 760 – 3000*

Aqueous 290 – 380* 380 - 760 760 – 3000*

Lens (child) 310 – 380* 380 - 760 760 – 2500*

Lens (older adult)

375 – 380* 380 – 760* 760 – 2500*

Vitreous 290 – 380* 380 - 760 760 – 1600** Partial transmission

Effects of Ultraviolet Radiation1) Photophthalmia Aka photokeratitis or photoconjunctivitis Photochemical damage to the corneal

epithelium Results from absorption of UV of 300 nm and

below

2) Pterygia , Pingueculae & Band Shaped Keratopathy

Result from repeated, long continued exposure to UV radiation

3) Cataract Cumulative effect of UV radiation UV B (290-320 nm) is main causative factor

Photo-oxidation of lens crystallinsPhoto-oxidation of lens membrane lipidsDamage to lens epithelial DNA

4) Retinal lesions

cataract

Effects of Infrared Radiation

Ocular Structure

Damage

Cornea Opacification , haze , debris, exfoliation

Aqueous humor Flare , cells , pigment

Iris Miosis , hyperemia , swelling , necrosis

Lens Cataract

Vitreous humor Haze or flare

Retina Depigmentation , edema , frank burn

Effects of Visible Radiation Normal levels of visible light not hazardous

Unusually high levels of visible radiation cause both photochemical and thermal injury to retina

Short wavelength – photochemical damage

Longer wavelength – both photochemical and thermal damage

Occupational ocular problems depend on Nature of the work Working environment

90 % of the occupational ocular hazards are preventable

Occupational ocular problems in sports

Sports – physical activity carried out under an agreed set of rules, with a recreational purpose: for competition or a self enjoyment or a combination of these

American Medical Association classifies sports as

Collision

FootballHockey Rugby

Contact baseball Basketba

ll Wrestlin

g Boxing

Non contactRunning Tennis

Swimming

OthersBowling

Golf Archery

On the basis of potential for eye injuries

Low risk sports • No use of ball, puck, bat, stick, racquet,

no body contact• Running, swimming, cycling, gymnastics

High risk sports• Use of ball, puck, bat, stick, racquet,

body contact• Baseball, hockey, football, basketball,

racquet sports, tennis, golf

Very high risk sports• Boxing, wrestling, contact martial arts• Eye protectors typically not worn

Common mechanism of eye injuries in sports

Blunt traumaPenetrating

injuries

Radiation injuries

Blunt Trauma Accounts for most sports related eye

injuries Extent of ocular damage depend on size,

hardness and velocity of blunt object Caused by ball, bat, stick, racquet used for

playing Eye hand collision in games like wrestling,

boxing, so on

Penetrating Injuries Relatively uncommon but may occur

even with large projectiles Range from mild abrasions to serious

lacerations

Radiation Injuries Occur as a result of exposure to

ultraviolet rays In snow skiing, water skiing and other

water sports

Use of protective eyewear , filters and performance sun eyewear help in the prevention of these hazards

Nature of athletic activity (contact or non contact) , weather and atmospheric conditions that may be encountered by athlete should be considered while prescribing protective eyewear and filters

Purpose of sports eyewear

• Protect eye from ocular injury and UV radiation

• Provide proper vision so that wearers can continue to perform with least discomfort while getting the right level of protection

Protective eyewear in sports

• Use of polycarbonate, Trivex , NXT lens materials can provide superior impact resistance over glass and CR 39 lens materials

• However the frame construction does not withstand the forces encountered in many sports

• Use of protective eyewear required to ensure adequate protection

Two basic types of protective eyewear designs available Goggle style Shield style protection attached to a helmet

Lightweight frame but resistant to strong impact

Fitted with an elasticated sports band

Made of impact resistant plastics, preferably polycarbonate

Glass lenses should be avoided

• Face-form (wrap) design sun eyewear offers improved coverage of the ocular surface tissues and a wider field of view than traditional designs

• The improved coverage increases UV protection by preventing light leakage around the frame and protects the eye from the harmful effects of wind and dust.

Protection eyewear used in some sports

1) Racquet Sports Includes badminton, handball, tennis, etc Ball or shuttlecock is hit with tremendous

force and can travel at speed of upto 90 mph

The eyewear must protect the eye and orbit from several angles including the sides

2) HockeyFull face shieldHalf face shield

3) Swimming and water sport• Most swimmers and divers use a goggle or

face mask so that no adjustment is necessary to the habitual prescription to compensate for the difference in the index of refraction of the water medium.

• Some goggle designs have ventilation holes to reduce lens fogging in highly active water sports such as water skiing, surfing, windsurfing, and endurance swimming.

4) Snow skiing Snow skier encounters a 15 % increase in

UVR for each km (3000 ft) of altitude above sea level

May lead to photokeratitis that might ultimately lead to snowblindness

Eyewear with UV filters should be used

Filters and performance sun eyewear

• Higher level of solar radiation in outdoor sports saturate the photoreceptors and reduce finer level of contrast sensitivity

• Properly selected filters reduce glare and improve contrast

• This enhance the ability to discern the crucial details and judge depth

• Protection from UV exposure

• Protection from light radiation is directly related to filter lens density

• Transmittance of filter defined in shade number (higher the shade no. lower the transmittance of filter)

• Select the darkest shade that allows the task performance

1) Neutral Gray Tints

• Absorbs all wavelength of visible spectrum almost equally, natural appearance of colors is preserved

• Preferred by athletes who are sensitive to color information in their sport and who do not appreciate even subtle alteration of the natural environment

• Often favored by those participating in golf, skiing, and mountaineering activities

• Athletes must make critical performance decisions based on subtle terrain details in these sports, and distortion of natural contour cues can lead to poor decisions

2) Yellow – Brown Range Tints

• Filter visible spectrum through the attenuation of the transmittance of the shorter wavelength colors

• Decreases the chromatic aberration between the longer red wavelengths and the transmitted mid-range greens

• Leads to improved image clarity, and the selective transmission of yellow wavelength light concentrates the visible information at the most sensitive portion of the visible light spectrum

• Filter the glare produced by short wavelength light

• Preferred in shooting, snow sports, tennis, baseball

3) Green Range Tints• Green portion is selectively transmitted• Preferred in golf, tennis, woodland shooting

4) Red Tints• Provides better color perception in low light

condition• Helps in contrasting object against blue and

green background• Ideal for night sports

4) Polarized Filters

• Reduce the reflected glare off the horizontal surfaces, water, snow, pavement, sand

• Useful in fishing, water sports, snow sports, cycling, driving

5) Photochromic lens

• Plastic photochromic lens suitable for some non contact sports like running, cycling

• Glass photochromic lenses not used

Contact lenses in sportsChoice of refractive correction in highly dynamic sportsDynamic sports – baseball, basketball, football, racquet sports, skiing sports, volleyball, gymnastics,etcField of view aberrationsVisual field restrictionsOptical distortionFrame discomfortFrame instabilitySurface reflectionsLens fogging

Largely avoided by moving optics on cornea

In aiming sports like shooting and archery, spectacles preferred over contact lens

Undesirable visual fluctuation on prolonged gaze due to lens movement on eye

Peripheral vision do not affect the performance

Contact lens movement decrease contrast sensitivity

• Soft lens with UV absorbing tints protect only the ocular tissues covered by contact lens

• Best protection when used in combination with quality sun eyewear

Occupational ocular problems in driving

Driving can be defined as the ability to operate, control and direct the course of vehicles

Normal visual functioning is an essential requirement for driving- drivers need to be able to judge the distance - read road signs and traffic lights - assists driver to respond to changes in environment quickly and efficiently

• Good visual acuity in addition to normal visual field, good stereopsis, normal color vision, eye co-ordination, good retinal adaptation are essential to avoid RTAs (Nwosu 1989)

• As driving is an outdoor activity, drivers are exposed to high level of radiations, dusty and windy environments

Common ocular problems:Pterygium Pingueculae Allergic conjunctivitisCataract Presbyopia Glaucoma (pattern of eye diseases among commercial intercity vehicle drivers in Nigeria Bola J Adekoya et.al Nigerian J of Opth 2008)

Protective eyewear in driving

For day time driving Sunglass lens that transmits less than 67

% of the incident light can be used

Excellent absorption in 200 to 300 nm portion of UV region

Inadequate absorption in 300 to 400 nm portion of UV region

Less than 15 % transmittance in range of 700 to 15oo nm

Maintain optimum retinal adaptation for night vision in night driving

Yellow, green and brownish lenses impair color vision significantly due to selective shift in the spectral transmittance of the lenses

so not recommended as sunglass lenses for drivers

Lenses with anti reflection coating Polarizing lenses- reduce reflection from

wet road and snow

For night driving

Only the lightest of the tints should be used

Poor illumination at night, and use of tint can further reduce illumination which is unsafe for driving

Antireflection coating on the lens with lightest tint maximize the transmission of absorptive lens

Increase in transmission caused by coating sufficient to offset the loss from absorption by the tint

Occupational ocular problems in agriculture

Agriculture includes crop farming, livestock rearing and fishing

Most of the agricultural works involves use of agricultural tools, fertilizers, insecticides and pesticides

Most of them are outdoor works

Main causes of agriculture related ocular problems :

direct trauma with agriculture tools

vegetable/plant/organic materials hitting the eye

chemical injuries by pesticides and insecticides

animal attack injury ( e.g cow horn injury , insect sting)

soil spillage into the eye

other foreign bodies in the eye

constant exposure to wind, dust and allergens

constant exposure to UV light

( challenges of agriculture related eye injuries in Nigeria, Community Eye Health Journal 2015)

Short term effects of UV exposure- photokeretitis , irritation

Long term effects- pterygia, pingueculae, cataract and retinal damage

Allergic conjunctivitis

Protection eyewear in agriculture

1) Sunglasses

2) Safety glasses- wrap around lenses

3) Goggles – protection from front and side impact

4) Full face shield

Occupational ocular problems in industries

Potential eye hazards are found in almost every industries

Common ocular hazards1) Mechanical injury- By flying fragments, objects, large chips, sand, dirt- Common in chipping, grinding, machining , sanding tasks2) Heat injury- By hot sparks, splash from molten metals, high temp

exposure- Common in furnace operations, casting, gas cutting,

welding tasks

3) Chemical injury- Common in acid and chemicals handling

tasks

4) Radiation injury- Common in welding electric arc, welding gas, cutting, brazing, soldering

Ocular protection devices for industries

These devices must protect the workers from1) Potential mechanical and chemical injury2) Possible radiant energy damage

Available in the form of1)Spectacles 2)Goggles 3)Face shields4)Helmets

1) Safety Spectacles

- Manufactured in both metal and plastic materials

- Provided with or without sideshields which protect eye against objects flying from the side

- May be supplied with plano lenses or worker’s RX

2) Chipping goggle - Aka impact cup goggle

- Useful in tasks involving chipping and grinding where foreign body may strike the eye from any direction

3) Impact or dust goggles- Made from a soft, flexible plastic material

that is molded in a single front

- Lenses inserted into the frame of eye cup to provide rigidity to goggle

- Designed to be worn over a pair of spectacles

- Perforated holes on the side of goggles extending from mask to facial area allow ventilation that prevent lenses from fogging

4) Chemical goggles

- Constructed the same as impact goggles except for ventilation system

- Consists of a series of plastic louvers designed to provide indirect ventilation while preventing chemical splashes

- May also be worn over spectacle lenses

5) Welding goggles

- Protect welder’s eye from impact as well as harmful radiation

- Welding helmet provides the required protection for the head, neck and eyes during electric arc welding operations

- There is a window through which the welder can view the welding process

- Window hold a series of filter for protection against UVR, IR and visible radiation generated by welding arc

6) Face shield- Protect the head, neck, face and eyes from flying particles and chemical and molten metal splash

Eye and Face Protection Selection ChartSource Assessment of Hazard Protection

IMPACT - Chipping, grinding, machining, drilling, chiseling, riveting, sanding, etc.

Flying fragments, objects, large chips, particles, sand, dirt, etc.

Spectacles with side protection, goggles, face shields.For severe exposure, use face shield over primary eye protection.

HEAT - Furnace operations, pouring, casting, hot dipping, and welding.

Hot sparks

Splash from molten metals

High temperature exposure

Face shields, goggles, spectacles with side protection. For severe exposure use face shield.

Face shields, reflective face shields.

Screen face shields, reflective face shields.

CHEMICALS - Acid and chemicals handling

Splash

Irritating mists

Goggles, eyecup and cover types. For severe exposure, use face shield over primary eye protection

Special-purpose goggles

DUST - Woodworking, buffing, general dusty conditions

Nuisance dust Goggles, eyecup and cover types.

LIGHT and/or RADIATION

Welding - electric arc   Welding - gas    Cutting, torch brazing, torch soldering  Glare

 

Optical radiation  

Optical radiation   

Optical radiation  

Poor vision

Welding helmets or welding shields. Typical shades: 10-14  Welding goggles or welding face shield. Typical shades: gas welding 4-8, cutting 3-6, brazing 3-4

  Spectacles or welding face shield. Typical shades: 1.5-3  Spectacles with shaded or special-purpose lenses, as suitable.

CONCLUSION….

• Majority of the occupational ocular hazards are preventable

• All protective eyewear have certain limitations

• Proper selection of protective eyewear depending on the nature of work and working environment helps in the prevention of potential eye hazards

REFERENCES

Environmental Vision, Interactions of the Eye, Vision, and the Environment-Donald G. Pitts

Sports Vision – Erickson Occupational and Environmental Vision- The

Role of the Optometrist in Occupational Safety and Health, Ralph G Chou

Internet sources Borish’s Clinical Refraction- William J Benjamin Clinical Optics- Theodore GrosvenorSolutions for Living: Personal Protective

Equipment for Agriculture- Randolph Weigel