The Cause and Effect of Agent Orange in Vietnam

                                                           Region Of Focus

2005 Digital Globe

                                                                                                                                                                                                            

                                   Spraying Agent Orange In Vietnam

Courtesy of The Associated Press

Courtesy of Associated Press

Courtesy of Associated Press

1. Abstract:

This research project aims to observe and assess alterations of the vegetation by using Color Composite, Normalize Difference Vegetation Index Grayscale, Density Slicing, and Change Detection. in the region of the Hot Spot Bien Hoa in Vietnam. In 1962, the U.S military initiated the use of herbicides in Vietnam for general defoliation and crop destruction through its program co named Operation Ranch Hand. Herbicides applied to the vegetation during the U.S occupancy was part of the war effort. Revises of documents have given new estimation gallons of Agent Orange and other chemicals utilize in the campaign. Over the course of 6,000 missions 10 percent of Vietnam was sprayed with Agent Orange. We will compare images from 1972-2005 and present our findings of re growth or infrastructure of the Hot Spot Bien Hoa.

Rainbow Dioxin Chemical Traces

2. Introduction 

        

Region of focus is Bien Hoa a city in Dong Nai providence,Vietnam.  Bien Hoa had been listed as a military instillation and one of the four Hot Spots of storage areas. The four areas are Bien Hoa, Da Nang ,Nha Trang, and Phu Cat.  Military installations are referred to a base, camp, post, station, yard, center, or the activity under the jurisdiction of the secretary of a Military department. The U.S stored bulk drums of Agent Orange in Bien Hoa military base throughout the campaign. The facility experience many leakages, but one incident had been documented. For instance, in 1970 a 7,500 U.S gallons spill of Agent Orange occurred on the base of Bien Hoa.

Bulk Storage Agent Orange Stripe visible on drum

Vietnam forests have been an inhabitant for fauna and exotic flora that have been around for many years. In 1959-1975 the habitat has change dramatically. For instance, there are many species that live in the Rainforest in Vietnam such as the red-shanked gibbon and saola that thrived in abundance at one time. These species have decline in numbers because of the spraying of Agent Orange along the forest and coastlines. Severe damage has mostly occurred in the mangrove forests of the coastal areas. These sites are still visible today. The Agent Orange has left the precious areas were coastal birds and fish once inhabited barren because of the spraying of Agent Orange 

Courtesy of Associated Press

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3. Method:

Initial processing 

To begin with we utilized Global Land Cover Facility University of Maryland Earth Science Data Interface (ESDI). Our preference of choice was Landsat Imagery .We then downloaded [Dataset] MSS, [ID] 027-800, [WRS: P/R] 1; 134/052, [Acq.Date] 1973-01-02, [Producer] EarthSat, [Attr.] Ortho, GeoCover, [Type] GeoTIFF, [Location] Cambodia, Vietnam. All data from GLCF needs to be extracted from a zip folder to input into ENVI software for further analysis. The earliest images that provided information to the study site were taken in 1973. The next step we downloaded Landsat imagery  [Dataset] TM, [ID] 013-157, [WRS: P/R] 2: 125/052, [Acq.Date] 1989- 01-16 [ Producer] EartSat, [Attr.] Ortho, GeoCover, [Type] GeoTIFF, [ Location] Cambodia, Vietnam. Landsat [Data] ETM, [ID] 039-821, [WRS: P/R] 2:125/052, [Acq.Date] 2000-11-06, [Producer] EarthSat, [Attr] Ortho, GeoCover, [Type] GeoTIFF, [Location] Cambodia, Vietnam. All of the imagery was carefully analyzed for noise (clouds) but was limited with four MSS images all showing clouds, whereas the TM and ETM are decent images to interpret. 

Image Compositing

We then showed a time series subsetted in the natural color. The next step was that our images needed to be converted from the “natural color” (3, 2, 1 Color Composite) TM, and ETM images to infrared (4, 3, 4 Composite). We did encounter a little problem with the MSS imagery. It could not be subset in the natural color because it lacks the blue band. Whereas subsetting in the infrared (4, 3, 4 Composite) MSS, TM, and ETM was more consistent to interpret with the next step involving NDVI grayscale composite method.

NDVI

After saving the infrared (4, 3, 4 Composite) subset images we converted to NDVI grayscale. A Normalize Difference Index (NDVI) grayscale analysis is a visually simplistic way to analyze the progression of vegetation regrowth over the 30 year period in Bien Hoa. We compared both imageries in the infrared, and grayscale side by side to show that white in the grayscale represents the strongest and black represents the weakest growth of the vegetation. 

Density Slicing

Through ENVI, the Normalize Difference Vegetation Index for each year supported our research and we decided to perform an analysis from a Density Slice model. Density slicing visually enhances radar differences based on image brightness. The density slice default is seven classes and we chose three classes for our model. In particular, ranges from 0.2500 to 0.5000 (Green) neutral growth range, 0.5000 to 0.7500 (Magenta) minimal positive growth 0.7500 to 1.000 (Cyan) maximum positive growth and black negative growth.

Change Detection

Finally, we were determine to present an additional method demonstrated through change detection analysis utilizing Compute Difference Map option. The compute difference map routine produces an ENVI classification image characterizing the difference between any of initial pair and final stage images. We modeled two time periods 1973 to 2000 and 1989 to 2000 to support our hypothesis.

4. Results 

01-02-1973   Infrared/ Red/ Infrared  Bands (3,2,3)  Landsat MSS

Unfortunately the MSS image does not have a blue band, therefore we cannot see in the visible. It is shown in 3, 2, 3  infrared. There is cloud noise in this image, but most importantly to the North on Bien Hoa Airbase there is vegetation in purple.

01-16-1989 Natural Color  Bands (3,2,1) Landsat TM

In 1989 we definitely see in the visible composite. There is some vegetation potential, but this image is in January. There are more infrastructures than vegetation shown in this image. The river shows maybe a lot of algae that thrives in the river.

02-13-2002  Natural Color Bands (3,2,1) Landsat  ETM

In 2002 the vegetation is thriving along with the urbanization or modernization of the  Bien Hoa Airbase.

01-16-1989 Near Infrared/Red/Near Infrared Bands (4,3,4) Landsat TM

The NDVI is created through a ratio of the TM/ETM bands 3 and 4 using the equation NDVI = (TM 4 - TM 3). NDVI was one of the first successful indices created based on band rationing.

02-13-2002 Near Infrared/Red/Near Infrared Bands (4,3,4) Landsat ETM

01-02-1973 NDVI Grayscale Landsat MSS

The NDVI’s shows white is greenest and black absolutely no green.

01-16-1989 NDVI Grayscale Landsat TM

02-13-2002 NDVI Grayscale Landsat ETM

01-02-1973 Density Slice Green/Magenta/Cyan Landsat MSS

The Density Slices in all images show 0.2500 -0.500 GREEN, 0.500 – 0.750 Magenta, 0.7500 -1.000 Cyan.

01-16-1989 Density Slice Green/Magenta/Cyan Landsat TM

02-13-2002 Density Slice Green/Magenta/Cyan Landsat ETM

1973-2002 Change Detection

The change detection shows the vegetation re-growth in existence, except for the huge cloud.

1989 - 2000 Change Detection

5.Discussion:

So what is this Agent Orange? Agent Orange is a 50/50 mixture of 2,4-dichlorophenoxyacetic acid (2,4-D), and 2,4-5 trichlorphenoxyacetic acid  (2,4,5-T). The 2, 4, 5-T fraction of the Agent Orange mixture contains the highly toxic chemical 2, 3, 7, 8-tetrachlorodibenzo – p – dioxin (TCDD). The powerful herbicide 2, 4, 5 -T which was is the main ingredient used in the defoliant utilized by the United States Military in the Vietnam War. During the war 40 million liters of Agent Orange including 400 kilograms of pure dioxin had been sprayed on trees in South Vietnam. Much of South Vietnam is covered with dense jungle vegetation. This dense vegetation was used as a cover by the forces opposing the United States and South Vietnamese armies. Three million Vietnamese were contaminated including thousands of American Soldiers.

Several soil samples analysis from Bien Hoa Airbase “Hot Spot” has shown that Dioxin levels decrease with the depth underground. It is evident that the concentrations in the soil and sediment from the spills  of (TCDD) in 1970 are very high levels. The top soil is approximately 0 – 30 cm in depth from the surface.  The upper levels usually contain large quantities of organic matter that is broken down from plants, and animals in the environment which quickly absorb the chemicals. Analytical tests have proven that composed inorganic matter such as clay and sand contain low levels of dioxins. It may be true that during the Vietnam War (1961-1971) the United States Military had experimented utilizing twenty chemicals manufactured by Monsanto for many different objectives. It is also known that only five of those chemicals or substances had been applied to areas by airplane, helicopter, trucks, riverboats, and backpack sprayers. The chemicals are also known as rainbow dioxin chemicals because of the different colors. For instance, Agent Orange (AO), Agent White (AW), Agent Green (AG), Agent Pink (AP), and Agent Blue (AB) all were present in South Vietnam. Among these chemicals three agents were utilized frequently. Agent Orange 1.77 to 40 ppm, Agent Blue 32.8 to 45 ppm, and Agent White 65.6 ppm. These names represented the color of the stripe on the barrel that was used to identify the herbicide.

The Republic of Vietnam was dived into four tactical zones, each of which was a political as well as military jurisdiction. The map below shows the amount of gallons sprayed in each corps. I Corps zone 2,355,322 gallons, II Corps zone 1,054,406 gallons, III Corps zone 4,086,229, and IV Corps zone 669,534 gallons sprayed through 1961 to 1971. The “HOT SPOT” Bien Hoa approximate applications was Agent Orange 35,045 gallons, Agent Blue 3,950 gallons, and Agent White 124,525 gallons for a total of 163,520 gallons sprayed from 1961 to 1971. Approximately 10% of Southern Vietnam was sprayed during the campaign. Although the war ended in 1975 it has been documented that adverse effects of the chemical residue on the Vietnamese people and ecosystems were evident. Studies on this subject are difficult to perform due to several factors. It has been over 35 years and land use disturbance, degradation, and of dioxin into biological food web. Revise documents have surfaced and some military documents have been released, but until all documents have been released test and methods will reveal more than we know.

 6 Conclusion: 

NEW INFORMATION: A study has increased the estimate of how much Agent Orange and other dioxin-tainted defoliant the United States military actually sprayed in South Vietnam. Although it is unclear whether the new study that has increased from previous amount raises the illness risk of those exposed, according to scientist. Researchers at the Columbia University School of Public Health determined approximately 21 million gallons of the herbicide was sprayed from 1961 – 1971. In fact 55 percent of the defoliant had been Agent Orange. Scientists have strong evidence that Agent Pink that is closely related to Agent Orange and it more potent was applied also. Vietnam scientists conducted their own analysis in 1999, but details were not made public. The researchers at the University of Columbia estimate that 2-1 million to 4.8 million people were living in 3,181 villages had been sprayed on directly.

7.References: 

 

Cau, 2003 Cau, H.D., 2003. Environment and human health in Vietnam – Years after the Ranch Hand Operation, Haoi

Dwernychuk, 2005 L.W. Dwrnychuk, Dioxin hot spot in Vietnam .Chemosphere, 60 (2005), pp 998-999.

Global Land Cover Facility, University of Maryland., 2011 Landsat MSS, TM, ETM., < http://glcf.umiacs.umd.edu/ >

Google Earth 2005 Google, Inc., < http://www.google.com/earth/index.html >

Stellman et al., 2003 J.M Stellman, S.D. Stellman, R. Christian, T Weber and C. Tomasallo, The extent and patterns of usage of agent orange and other herbicides in Vietnam. Nature, (2003), p 422

Verrengia, Joseph. Associated Press April 16, 2003 < http://www.ap.org/aparchive/index.html>.