diff --git a/src/display/api.js b/src/display/api.js
index 19ea589fd..b5ad2851c 100644
--- a/src/display/api.js
+++ b/src/display/api.js
@@ -574,9 +574,7 @@ class PDFDataRangeTransport {
  * properties that can be read synchronously.
  */
 class PDFDocumentProxy {
-  constructor(pdfInfo, transport, loadingTask) {
-    this.loadingTask = loadingTask;
-
+  constructor(pdfInfo, transport) {
     this._pdfInfo = pdfInfo;
     this._transport = transport;
   }
@@ -761,6 +759,13 @@ class PDFDocumentProxy {
   get loadingParams() {
     return this._transport.loadingParams;
   }
+
+  /**
+   * @return {PDFDocumentLoadingTask} The loadingTask for the current document.
+   */
+  get loadingTask() {
+    return this._transport.loadingTask;
+  }
 }
 
 /**
@@ -1827,9 +1832,8 @@ class WorkerTransport {
     }, this);
 
     messageHandler.on('GetDoc', function({ pdfInfo, }) {
-      this.numPages = pdfInfo.numPages;
-      this.pdfDocument = new PDFDocumentProxy(pdfInfo, this, loadingTask);
-      loadingTask._capability.resolve(this.pdfDocument);
+      this._numPages = pdfInfo.numPages;
+      loadingTask._capability.resolve(new PDFDocumentProxy(pdfInfo, this));
     }, this);
 
     messageHandler.on('PasswordRequest', function(exception) {
@@ -2130,7 +2134,7 @@ class WorkerTransport {
 
   getPage(pageNumber) {
     if (!Number.isInteger(pageNumber) ||
-        pageNumber <= 0 || pageNumber > this.numPages) {
+        pageNumber <= 0 || pageNumber > this._numPages) {
       return Promise.reject(new Error('Invalid page request'));
     }
 
diff --git a/test/unit/api_spec.js b/test/unit/api_spec.js
index 56d744d6b..5cd662d28 100644
--- a/test/unit/api_spec.js
+++ b/test/unit/api_spec.js
@@ -954,7 +954,7 @@ describe('api', function() {
         return _checkCanLoad(false, filename, options);
       }
       afterEach(function(done) {
-        if (loadingTask) {
+        if (loadingTask && !loadingTask.destroyed) {
           loadingTask.destroy().then(done);
         } else {
           done();
@@ -1385,7 +1385,6 @@ describe('api', function() {
     // A PDF using the Arial font.
     var pdf3 = buildGetDocumentParams('issue6068.pdf');
     var loadingTasks = [];
-    var pdfDocuments = [];
 
     // Render the first page of the given PDF file.
     // Fulfills the promise with the base64-encoded version of the PDF.
@@ -1393,7 +1392,6 @@ describe('api', function() {
       const loadingTask = getDocument(filename);
       loadingTasks.push(loadingTask);
       const pdf = await loadingTask.promise;
-      pdfDocuments.push(pdf);
       const page = await pdf.getPage(1);
       const viewport = page.getViewport({ scale: 1.2, });
       const canvasAndCtx = CanvasFactory.create(viewport.width,
@@ -1413,18 +1411,10 @@ describe('api', function() {
       // Issue 6205 reported an issue with font rendering, so clear the loaded
       // fonts so that we can see whether loading PDFs in parallel does not
       // cause any issues with the rendered fonts.
-      var destroyPromises = pdfDocuments.map(function(pdfDocument) {
-        return pdfDocument.destroy();
-      });
-
-      // Destroy the workers.
-      var destroyPromises2 = loadingTasks.map(function(loadingTask) {
+      const destroyPromises = loadingTasks.map(function(loadingTask) {
         return loadingTask.destroy();
       });
-
-      Promise.all(destroyPromises.concat(destroyPromises2)).then(function() {
-        done();
-      });
+      Promise.all(destroyPromises).then(done);
     });
 
     it('should correctly render PDFs in parallel', function(done) {