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Geography
Toxicology and WNV Encephalitis
New York City Region - 1999

The epidemic epicenter could have happened anywhere. It occurred, however, in one of the most congested, polluted areas of the United States, during a summer of record-high air toxics levels for that area.

Toxicological epidemiology is difficult due to a carefully maintained unavailability of data. So, in an effort to put the picture together piece-by-piece, public literature has been reviewed. The human epidemic first occurred, and mainly occurred in northern Queens, e.g., Whitestone, College Point, and Bayside (this is the order usually stated). The epidemic began in northern Queens zipcode 11357 (represented by the red cross) and then "spread" to the secondary epicenter, across the bay, to the SE Bronx rather than to adjacent land areas. Secondary areas for human cases and crow deaths were in the SE Bronx.

During the summer, beginning late- to mid-June, unconfirmed reports of crow deaths indicated that the peak of crow deaths occurred before August, 1999, before the human epidemic began.

During late July and early August some officials noticed and were notified of large numbers of dead crows. Many of these were reported to the NYSDEC from northern Queens. The areas south of the Whitestone Bridge and south of the Throgs Neck Bridge were mentioned, and Fort Totten (on the point just to the east of the Throgs Neck Bridge) were mentioned as sites of numerous crow deaths. Throgs Neck in the Bronx was also mentioned.

About a week later, August 12, the first human cases began to file into Flushing Hospital from the Whitestone area (see 3 red crosses below). The epidemic is summarized by borough:

NYC Patient Statistics as of 10/7/99 (ref)
Status			Age			Location
Hospitalized	5		60 or more	29		Queens	27
Deceased	4		50's	4		Bronx	9
Discharged	30		40 or less	6		Manhattan	2
						Brooklyn	1
Totals	39			39			39

As of May, 2000, the figures have been slightly revised by the NYCDOH:

NYC Patient Statistics as of May, 2000 (ref)
Location
Queens	32
Bronx	10
Manhattan	3
Brooklyn	1
Totals	46

From the literature, descriptions of the epidemic epicenters have been approximated in the map below. The major human epicenters, as described, are circled in black and the major crow epidemic centers are squared in blue. Each of the 3 red crosses represent a middle point of 3 zipcode areas (ref) described by NYSDOH as the areas of the outbreak epicenter. Generally, winds come from the north and from the west. The following represents northern Queens (College Point, Whitestone, and Bayside) in 1999:

(Legend)

As of 1999, the entire borough of Queens contained only 3 EPA air toxics station monitors, represented by black squares. College Point had 2, and Bayside had 1. A sudden increase in the number of monitors is being completed for the end of the summer of 2000.

All boroughs are represented in the following table:

It is interesting to note that mosquito-virus surveillance systems are now being established in New York City and that there is a parallel increase (time and place) in the number of pollution monitor stations. It is also interesting, possibly from a political viewpoint, that much of the highly polluted SE Bronx has no station monitors.

The SE Bronx community has relatively little political power to resist a severe encroachment from industrial sources of pollution, according to my interview of community board leaders who expressed frustration and ire. Ash and fiber pollution can be seen in SE Bronx window screens and air fans, if they are not frequently cleaned, the evidence of incinerator emissions. Such material is seen much less in Manhattan where an ever-settling fine, black carbon settles daily on floors and window sills, the evidence of diesel and powerplant emissions.

For a wider perspective, refer below to a map of New York City (not showing the two southern boroughs of Brooklyn and Staten Island). New Jersey is in the very NW corner, Manhattan to the west, being just south of the Bronx, and the large borough of Queens to the east (1999):

Legend
White circles	College Point, Whitestone, Bayside (Queens)
Dark circles	Vaguely described areas of cases in Manhattan, and SE Bronx
Blue Squares	Crow deaths
	EPA monitor stations
	Center of zipcode areas of epidemic epicenter (ref)

Dead crows were found throughout the New York region, including Long Island, but the first, prominent, and the most numerous findings, which were brought to the attention of the NYSDEC and deemed worthy of media attention, are represented above with blue-squares.

The exceptional concentrations of human and crow deaths correlate well with areas of highest levels of ozone and MTBE pollution -- near pollution monitors, multiple expressways, downwind from La Guardia Airport, and the toll gates of the bridges. According to the EPA Region #2 office (NYC region) the College Point monitors were installed to monitor the airport. Take-offs and landings occur from both runways.

Aircraft Emissions

The following is derived from the EPA's "Final Report: Evaluation of Air Pollutant Emissions from Subsonic Commercial Jet Aircraft", April 1999.

LTOs are "landing and take-off cycles", used to evaluate emissions from airports. New York City region is second in the nation to Chicago in total LTOs per year. The greatest number of LTOs/airport in the New York City area occur at La Guardia Airport, about 3,000 feet from the epidemic center, close to residential neighborhoods.

NYC leads the nation in aircraft NOx emissions (NO1, NO2).

"NO2 is an important precursor to both ozone and acidic precipitation, which harms both terrestrial and aquatic systems. Emitted from hydrocarbon combustion at high temperatures, NO and NO2 (collectively called NOx) react with gaseous hydrocarbons to form ozone.The mixture of NOx and urban air is commonly called 'smog'."

The following two tables include years 1990 and 2010:

By interpolating EPA data from the two tables and comparing with regional data,

it can be estimated that in 1999, approximately 3% of total New York City mobile sources of NOx were from aircraft, and about 1% came from La Guardia airport.

For La Guardia Airport, 1999, we can interpolate the first two tables giving 156,455 LTOs, and a total aircraft emissions of over 19 tons per day.

"The analytical results of the study confirm that commercial aircraft emissions have the potential to significantly contribute to air pollution."

Apparently MTBE is not added to turbine fuel, nevertheless, the components listed above are the basis for photochemical smog and ozone.

Most of the emissions come from take-offs, when the engines are running at full throttle. La Guardia has short runways and aircraft must ascend at a steep angle, driving their exhaust downward until they reach beyond the ground air "default mixing height" of 3,000 feet.

There are 4 possible take-off directions from La Guardia and direction 130 (SE), near Whitestone, is the most frequently used, representing 40% of all take-offs. Direction 220 is rarely used for take-offs (possibly to abate noise), and thus, whenever the wind is blowing from SW, S, or SE, runway direction 130 would be preferred. Many of these wind directions could move exhaust towards the epidemic area.

The composition of the aircraft emissions, VOC, NOx, SO2, and CO, combine and react in sunlight to form neurotoxic photochemical smog (ozone and aromatic nitros/sulfides).

An excellent summary of pollution in Queens is online at Queens College School of Earth and Environmental Science where it is stated:

"Airports create smog; a single 747 arriving and departing... produces as much smog as a car driven more that 5,600 miles, and as much NOx as a car driven almost 26,500 miles (source: Natural Resources Defense Council)."

Queens College provides a map showing La Guardia arrivals and departures and aircraft heading changes. I have included a modified version, showing the total number of departures (most pollution) and exhaust plumes on runway 13. I left out departures on runway 22 because they were relatively insignificant. Perhaps departures on 22 were deemed an avoidable source of noise pollution.

Queens College School of Earth and Environmental Science		Modified to Show Departures and Exhaust

Runway 13 has by far the most departure traffic. These numbers include all traffic, turbine and piston, making MTBE also relevant for consideration. The EPA states that gasoline formulations using up to 100% MTBE have been tested successfully for piston-powered aircraft.

Departing aircraft that bank to the right, away from the epidemic area, to perhaps avoid noise pollution over that area, ironically would be pointing their high velocity exhaust down and into the epidemic area. Additionally, winds from S, SSW, SE or E would necessitate departures on runway 13 so that planes can depart into the wind. Any winds from the southern directions could blow the exhaust plumes further into the epidemic epicenter of Whitestone and College Point, ensuring high levels of ozone during year 1999, and acting synergistically with MTBE gasoline formulations to produce an unprecedented smog characteristic.

Two Maps Superimposed Showing LGA Exhaust/Wind

From the beginning and throughout the main part of the epidemic, just preceding the early acute and fatal cases, during haze (pollution) days, the LGA weather station shows wind directions to be primarily from the southern directions.

Minute amounts of volatile organochlorines have been found to act in combination with ether (MTBE), VOCs, and oxygen to concurrently cause both fatal encephalitis and virus proliferation. (See Middlesex Study) There are numerous sources of organochlorines near the epidemic epicenter:

Reformatted data from the Queens College website:

Other High-Output Sources in Queens (1997)
Source	Emission	Amount
Abbott Industries, Inc., 95-25 149th St, Jamaica	Tetrachloroethylene	25,700 lbs
Tudor Handle Corp., 43-02 38th St, LIC	Toluene	12,341 lbs
Volkert Precision Products, Inc., 222-40 96th Ave, Queens Village	Trichloroethylene	3,750 lbs
Standard Motor Products, Inc., 37-18 Northern Blvd, LIC	Copper	50 lbs

The EPA report describes ozone poisoning:

"Acute health effects of ozone are defined as those effects induced by short-term and prolonged exposures to ozone... Acute health effects have been observed following prolonged exposures during moderate exertion at concentrations of ozone as low as 0.08ppm... Furthermore it is recognized that some individuals are unusually responsive to ozone and may experience much greater functional and symptomatic effects..."

This descriptions of ozone on the EPA sites do not emphasize the combined effects of VOC, NOx, SO2, CO, and particulate matter, i.e., their synergistic neurotoxic effects when combined with ozone in photochemical smog. Nor do they describe extra-pulmonary dysfunction, such as microscopic destruction of the involuntary nerve system that controls breathing, coordination, thought, and gastro-intestinal functions.

The levels of ozone at College Point were often in the range of 0.08ppm for a duration of months. (see Hourly Ozone Charts)

Summary

The upper New York City region appears to have its own capability to produce substantial air toxics. The following is an EPA AirNow ozone map (downloaded 2/19/2000), where the epidemic epicenter (northern Queens, the Bronx, and Bergen County) show an independent ability to produce high levels of ozone on 7/14/99:

EPA AirNow (7/14/99) dnld:2000.02.19

The next day, 7/15/99, the entire region showed high levels of ozone, with an "unhealthy" dark red accent across the epidemic areas:

EPA AirNow (7/15/99) dnld:2000.02.19

As of at least July 2000, when I attempted to again access these maps, I found them grossly revised by the EPA. In the new versions, the 7/14/99 map is completely green. The 7/15/99 map has been attenuated across the epidemic area. See Map Changes.

For more maps, see MapMuse (400KB) and RoadDensity/DeadBirds

Proposed Study

A study is proposed to examine historically (before 1999) the epidemiology of northern Queens and Bronx, in terms of neurological diseases, and comparing them to the surrounding areas. I would predict findings of higher incidence of non-WNV encephalitis within the WNV epidemic areas, thus demonstrating that something other than the WNV was responsible for the epidemic, and possibly all neurological diseases in the region. Historically, New York City in general has been a region of record-high incidence for neurological disease epidemics.

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